Well, I just got the Hero on Android 2.1 and frankly i'm disappointed.

Despite what the advocates say, I find it a cumbersome and complex OS. The memory on is low, and it wouldn't even let me take a photo without an SD card installed.

You're right on the task switcher, you can't actually close anything, instead Android does it for you - a big pain to me. I installed a task manager to kill running apps. The virtual keyboard is hideous, it looks nice but using it is so, so slow, but that might just be because i'm used to tapping away on the physical keyboard. As for videos and memory, we all know nothing even compares to the N900 on that front - 32GB built in, take take at least a 16GB card, and it supports more media formats than anything else.

My main gripe with Android is that it's so fragmented, and honestly, I don't see it lasting long. I fully agree with Nokia's statement that it's like peeing in your pants to keep warm - lots of manufacturers are jumping on it as a lifeline, but there's nothing to differentiate any of them. That's why i fully respect and agree with Nokia's decision to forge ahead with their own OS, so they maintain visbility in the market place and offer something different. If they offered Android as their main OS, i'd stick with my N900 until it stopped working, honestly.

Judged on your requirements i'd say Maemo 5 is for you, but, given that it's being phased out for MeeGo that might put you off. That being said, the fact it's a year old and being discontinued means you can get it pretty cheap now.