+Abdul Kahar Kamaly
I hear that a lot but then I read the xda thread or the rom thread on xda and there's always something that doesn't work quite right (usually the damn camera) and I rapidly lose interest.
That and there are a couple of things I do like on the Samsung stock rom which would be lost, such as the video player.
To see what the fuss is about I installed the latest CM rom on my Desire. Not bad at all, nice and fast but unlike pretty much any other rom it doesn't come with app2SD+ in fact i'm pretty sure it uses even more internal space than the stock rom, that just means more messing around on my end to make the phone usable again.+Nigel Jones
The wifi one is a big one, and an obvious one that should have never gone to release.
There's also the changes to the touch screen sensitivity, it's just not as good as it was on Gingerbread. (make some very small movements on both roms and you'll see what I mean)
But my favourite.. by a long way.. is the completely broken storage management. Some apps just can't see the internal memory properly any more. If you haven't come across this then you are VERY lucky because I estimate that around 20% of my apps cannot be installed/updated (you get an insufficient storage error) without first unmounting the SD Card and it's just frustrating.