Got a Nexus atm and the Android OS is a clusterfuck
What don't you like about it?
The UI lag.
All the UI glitching that happens around the place. (e.g. the UI for my messaging app screws up every other time)
The call log bugs (dials person Y when I selected person X)
Reception bugs (when I have full reception but everything directly goes to voicemail)
Bluetooth bugs (music skips when played over bluetooth)
Phantom SD card mounts/unmounts
Slow, *SLOW* transfer speed to computer
Dodgy wifi tethering (loses connection every 5 seconds)
Lack of accessories (you try finding a good functional case like
this one for any Android phone, and don't invoke the "you can buy a motorola defy if you want waterproof" argument)
...I could go on.
And this is not just my phone (Xperia S, ICS), but across the board for the Galaxy range (S II, Nexus, S III), the HTC range, etc etc.
The only reason I remain on Android is because it's cheaper (and when I signed the new contract in April, iPhone 4S was beginning to become obsolete). An open-source, advanced mobile OS is an excellent idea, but there are some fundamental design philosophies in Android that I disagree with (UI priority, music playback priority).