Post Revisions feature is poorly implemented. They're not thinking of the diversity of WP users that exists now. It may be fine for people who just use WP as a personal diary type of blog, and maybe they revise a post 3 times for minor edits, but it is not necessarily good for people who use WP to build other types of websites, and that is getting more and more common. WP should make itself flexible for alternative users. I recommend disabling it via manual wp-config technique if you're a power-user, for example a live-sports website where you update each Post some 100-200 times as the game develops (just one example of an ordinary sort of WP user who who revises a single post dozens of times, this may not be common but it is not unheard of or unreasonable to want this ability).

The radically increased size of the database makes backups more unwieldy. It makes backup files bigger (and some of us back-up daily). It is multiplied if you keep several blogs within the same database (using different table pre-fixes, a long-standing feature of WP). If you wanted to do a selective search-and-replace of some word in your database it would now take much longer to sift through multiple copies. The way they implemented it without an option to limit the amount of Revisions saved, has driven away some users & is giving bad publicity to WP.

It also broke the #1 podcasting method that existed in the World before this feature: PodPress plugin, on WP blog, was the leading method to Podcast, until this feature broke PodPress for untold 1000's of users. You can blame PodPress's developer for not updating on a moment's notice, if you want, but WP should have looked at this and helped save PodPress in order to remain the best podcasting platform. Instead WP just suddenly debuted this feature that no one understood, and they looked away while PodPress faded, leaving it to 3rd parties to solve how-to-podcast in WP 2.7+ (and there's still not a really great solution, wheras 2 years ago anyone would tell you that PodPress on WordPress was a great solution for podcasting).

Some of the developer types are as stubborn as a mule on this question particularly on the "support" forum. That has also driven people away. They need to learn some marketing & public relations basics, and look at the big picture instead of getting so excited to whip out a new feature on short notice. Matt M. should make it his personal job to step back & look at the big picture. Yes this feature is cool, but is it production-ready? Does it break stuff? Is it good for the wide world of WP users that we have & that we want to switch over to WP in reality?