OK, you have some reasonable ideas for your humour and you have the makings of some good jokes and, in a few places, you are demonstrating an excellent grasp of how to keep things amusing. However there are a number of issues that I feel are adversely effecting the humour in this one, this first thing that struck me was that you seem uncertain where your humour is coming from and thus your article feels inconsistent and the humour doesn't have quite the impact I suspect you were hoping for. Permit me to expand, consider your very first paragraph you start off well but quickly start trying to explain a lot of things to the reader at once while simultaneously trying to introduce a narrative style, the substance of what you are trying to do is good but your execution of the humour feels slightly off. Considering the first half of the article your context is very thin on the ground which is part of why the above is an issue, as a reader I was uncertain who was supposed to be presenting the article to me, are you trying to sound like a member of the Mafia or simply someone who is very aware of them, you seem to go in both directions as the article goes on and I would encourage you to take some time to decide where you want the humour to come from. What I mean by this is simply make it clear who is bringing the article to us, I'm not saying write at the start "Hello, my name is Tony and I work for the Mafia and before you can serve us you ought to know a bit about us" but simply that you consider the structure. Starting with something like "Hey kid, yeah you, you've just started helping the family out right? Let me fill you in, etc etc" Now while that isn't particularly brilliant I hope it communicates what I'm suggesting; you need to give the article some kind of context otherwise it sounds confusing, especially at the start as the reader is unsure where the jokes are meant to be coming from. I think that the style of humour at the start where you refer to the Mafia as an almost non-profit organisation is excellent and that sort of humour should be expanded, referring only very loosely to the activities of the Mafia and making them sound like they are ultimately for the greater good,
The other issue I had with your humour is that it is somewhat random especially in the "History" section where it is obviously made up, now there is nothing wrong with random humour or with making things up, however in my experience I have found that the best way to do such humour is to try and keep it as close to the truth as possible, and then draw your humour from there. For instance if I were to say "Darth Vader was born in 1983 to a Slag who abandoned him in Hollywood where he went on to appear in Star Wars as himself" it can be good for a brief laugh but it isn't likely to appeal to everyone, something like "Darth Vader was born a slave on the Desert planet of Tatooine, which is probably why he started killing people at such a young age" Again, while that is not the zenith of brilliant humour it is more likely to appeal that the first simply because it is a satirical take on what actually happens rather than something that has been made up. If you are unconvinced then you should consider why people will come to your article, they will come expecting a humorous take on the history criminal society rather than a made up story with some Mafia names dropped in. My suggestion is that you use the wikipedia summary of the history and satirise it, especially if you are having difficulties, alternatively you could shift the focus away from the history of the group; the decision is completely up to you, my feeling is simply that it is going to be far less appealing as it is now. A similar philosophy can be applied to the history of the other mafia groups. Try and decide how you want the article to sound and who you want to impart the information to the reader, and then decide how the humour in the middle of the article should work. I realise there is a lot to take in here, and I would urge you not to be discouraged, you have demonstrated you can write well and all you need to do is effectively direct that ability into replicating the stuff that works well and cutting down on the stuff that doesn't.
You have a pretty good concept and I'm interested to see how you can develop it, the main issue here is that you need to decide what tone your article is going to take. This links into what I said above about getting context for your article your tone is essentially whether the article is related as though it is being read from an encyclopedia: formal and information oriented, like this article or informal and related from the first person perspective like this one. The issue at the moment is that you are switching between the two as you go and ideally you should only have one. The switching makes the article seem incoherent and you should do your best to avoid this as much as you possibly can. My recommendation would be that you have a crack at the informal tone as you seem to already be closer to that one than to the other. If you need any help then take a look at some other articles written in that style, feel free to ask me if you are looking for recommendations of good ones,and use HTBFANJS too, not because I think you need it but simply because there are some brilliant tips in it to help you get a quick laugh from a reader.
Prose and formatting:
Not too bad, the prose that you have already don't have too many errors, my recommendation would be that you proofread your article carefully or, if that idea does not appeal to you feel free to ask one of the folks over at UN:PS to do it for you. Your formatting isn't too bad and my main suggestion is that you consider spreading the images out to ensure the text doesn't get crushed into the middle of the article. You may also want to trim the "See Also" section down a bit to about four links as a long list distracts attention away from the main purpose of the article, you should also try all the red links as there is no need for them and they just look untidy.
Your images are OK, my only suggestion would be that you try and bind them a bit more closely to the text in the article as the images should compliment the text rather than make a completely separate point. The images I take issue with are the last two they just didn't strike me as fitting in well with the direction you seem to be trying to go with the article. I daresay you will have plenty of choice of different images should you decide to change them, you can find some good topical images by simply raiding the wikipedia article and seeing what images they are using. My main advice is that you use your judgement to make the images work, if you are particularly attached to the current ones then you focus on the captions. Your captions can make or break your images so don't take them for granted and put plenty of thought into them.
My overall grade of the article.
Overall I felt that your article is on the right lines, your writing is good and you demonstrate an ability to write funny stuff, the main issue is that you are trying to do far too much with it. My best advice is that you simplify things and spend some time deciding where you want to take the article, do you want to tell the information with a story? Or do you simply want to explain it? You should choose carefully, but feel free to experiment with both. I realise there is a lot of criticism here and would encourage you not to be discouraged by it, I think you could have a serious VFH contender here with some work in the right places, all you need to do in order to achieve it is apply yourself and try and get as much feedback as you can from other users. If you have any questions or comments for me then all you need to do is ask me on my talk page. Good luck making any changes.