I have the same problem as parousia and insertclevername a few postings back. Since instaling 10.2.5 about 3 days ago, I have been unable to recover after putting my imac 17" to sleep. On "waking up", the screen flashes all kinds of junk, looking to me like memory has gone crazy. Nothing I tried could recover the system, nor could I get a restart - had to pull the plug or shut it off using the on/off switch then restart.
I assume this is a bug in 10.2.5, as sleep was ok in 10.2.4. Instead of sleep , I look at pretty pictures using "Screen Effects' from the System Preferences. Hoping that Apple will fix this soon, as I get a hassle from the wife whenever I waste electricity, no matter how little.
Except for the problem with the sleep function which I can live without till the next update, I am delighted with 10.2.5. It seems to work faster than the earlier one, and has been very reliable. I like it better than the last version.
I just had another kernel panic after waking my machine up. In my case, it only seems to happen when the machines is asleep for an extended amount of time but considering that I rarely turn the thing off it is freaking annoying.
I'm having an intermittent problem with sleep on my 17" iMac, but not the same as others. I can recover fine after sleep, no major issues. The only odd thing I noticed is my computer waking from sleep without me asking it to. And it seems to be right after I put it in sleep. For example, yesterday, I put my computer to sleep, the screen shut off, I turned around, and my screen came back on! ??? So I put it to sleep again, and it stayed there. Happened twice so far.