Gus, thanks for pasting the text from the post here (and hookem12387, sorry for the overwrought and overly-long presentation...I have a tendency to overwrite, especially when I'm not editing, like right now...
). I think hookem and bourbonbasted are absolutely on point here, and have distilled the essence of my post in far fewer words.
I wasn't necessarily trying to cast stones in my letter, just point out that whatever utility #menswear used to have (and it did have some, to me at least) as a place of inspiration has been eclipsed by the fact that it really is, as bourbonbasted says, "more-or-less a big circle jerk of cross-promotion." But, to be fair, tumblr doesn't really pretend to be anything other than a social networking site, and one that (if it isn't already) wants to successfully monetize. It just happens to be really easy to use and great for hosting a blog on--I know if it weren't for the ease of tumblr's use, I wouldn't likely have a blog at all.
I try not to look for more from tumblr than it proclaims to offer, but I do think there's value to be gained from highlighting the fact that the #menswear tag is decreasingly filling the space it used to fill for many of its faithful followers, and I can't but think that tumblr ought to be interested in knowing that the tag now, in the eyes of many, serves little purpose other than to generate hype for a select number of bloggers/designers/photographers and their friends, and that this is a turn off to a lot of people. Really, 'reforming' #menswear isn't really the issue either, since it is what it is, and that is determined by tumblr, and they are clearly in the "cool with it because it generates hits" mode right now. But, I know there's a ton of tumblrs out there doing awesome stuff, and it's just going to be harder to find and follow them now, but not impossible.