The intro is very good, as are all the self-referential sections, but of course it's not really laugh-out-loud funny, and it doesn't need to be. I spent most of it reading through thinking "yeah, that's clever", but it was more recognising your acute observational skills in picking up on key aspects of Leone's directorial style than actually finding it funny. I know this is how your articles generally work (and I love Ingmar Bergman, so it still doesn't detract from the quality of the article), but it's the one (minor) shortfall for me regardless. I do think more funny could be included, it is far from exhausting the comedic potential, but I can't think of anything at the moment, which just shows what I know.
Well, the concept - a film director article - obviously isn't a novel concept and the mode of representation is a tried-and-tested approach of course, but you've proven once again how effective it is. You emphasise the key stylistic aspects (credits/shoot-outs/cinematography/neverending supply of mexican bullet-fodder) in a neat way, all the facts are there, there is certainly nothing about Sergio that I feel you have missed out.
Prose and formatting:
Prose and formatting is excellent, its a key part of what makes your articles so good. The attention to detail of Morricone's score/sound effects in onomatopeic italics, the neat positioning and sizing of images (especially in the shoot-out). Couldn't be better really.
All the pictures mirror the text well, visuals are obviously important in this kind of article and your selection is spot on. None of them are doctored, but that's not your style anyway (and in most cases wouldn't suit your style at all). As I said before, the positioning and choice of pics for the shoot-out is particularly good. Actually I didn't get the significance of the last picture - that's Il Cattivo in the bath scene, right? I just feel it's a bit of an anti-climax...
Not sure what to put here, just thought I'd mention that I feel the ending is actually a slight anti-climax, but that's probably because the rest of it is such high quality, I keep expecting more to come. I haven't actually seen any Leone post-Spaghetti Western period (I have "...in America" to watch, somewhere) but I felt a little could be said about his later career works. Of course knowing what and what not to talk about is a grey area, to most people Leone's all about the SpagWesterns, so I can understand why you left it here. I think ultimately you're justified in doing so, it could quite easily become cluttered and superfluous, so you've actually sticked to what is most important very well.
Another great article for another great director, although I do feel a little there is more that could go into the humour side about the substance and recurring elements of his movies (just little observations perhaps), beyond the moral ambiguity of the characters, but that's purely subjective and I'm just being incredibly pedantic - it's definitely feature-worthy as it is.