I trust you whooami. So will you do it?
My personal reason is I cannot bear uploading TinyMCE, it has too many files and my FTP tends to disconnect mid-way for reasons I couldn't figure out. Then I have to start the upload again and it has to check every file again to see which ones didn't finish. It drives me batty watching 3 million file names and TinyMCE folders scroll thru my FTP log.
And I don't even use TinyMCE. I dislike it (to put it kindly).
The broader general reason is, why should every WP user (how many are there? Let's just pretend 500,000) upload ___kb of files, taking ___ minutes... when we really only need ___kb and ___ seconds to upload the 20 files that changed. Multiply by the # of users and that is an incredible amount of wasted time and bandwidth. Granted, time and bandwidth are free: it's the headaches that cost.
As for the trust issue, I would trust WordPress.org to post a Full Complete WP 2.2.2, and a special ZIP of updated-files-only for current users upgrading specifically and exclusively from 2.2.1 to 2.2.2.
Or I would trust a well-known third party, such as yourself, or the other blogger who posted the changed files when we went from 1.5.x to 2.0 (I forgot their blog name). I would also determine trust based on # of people who already tried it. In a community like this, if 5 people try it and it is a scam then we'll find out. If 15 peole have used it successfully and posted glowing Comments, I would not worry about trying it. We do this with Plugins and Themes all the time, which could have similarly devastating effects if it was a scam.
For me it's the difference between being EXCITED to install an upgrade, versus dreading it to the point of not doing it for several weeks until I have plenty of time to watch the FTP log scroll 3 million times.
The short answer is: the upgrades with WP are so frequent that it's annoying to reupload all the same files again and again, if they are not different.
Thanks for your reply.