Things i like about the device are:
* Divx video fullscreen playback looks fantastic
* VGA video recording at 30fps - the videos look great
* Audio quality of the mp3 player is very good
* The general menus are clean, easy and fun to use
* Good form factor
* Google maps is pretty cool if slow
* The Google Mail mobile app works well on this device (Initially I couldn't install it due to a missing certificate - to do that I installed Opera Mini 4 beta, clicked a link to download the certificate from somewhere, and then the mail app started working. Opera Mini 4 beta has susequently stopped working...)
Things that bother me:
* SSL is not supported for IMAP email access
* The excellent full screen keyboard does not function throughout the interface but only sometimes in the supplied browser. Edit - you can use it for writing text messages and for writing memos. Its probably in the built in email client as well but thats not working for me.
* Despite HSDPA (I'm on t-mobile with good reception), web browsing is slow, I think because page rendering is slow. I read somewhere that the processor is ~150Mhz so that would explain it (Edit - Opera Mini 3 actually works quite well).
* The supplied browser generally browses the WAP web. Someone said this is easy to circumvent, but I can't work out how to do that.
* Youtube videos are scaled down for this device and look rubbish. Also only some of the youtube videos are available. Browsing youtube in classic mode does not work.
* The still camera does not seem great to me although I have not used it much (I had a SE k750i before)
* 2GB limit on external memory
* No obvious LG support for this device - they could add IMAP SSL support and raise the 2GB limit in new firmware - but try googling for KU990 firmware and see how far you get! I'm guessing even if they make new firmware they wont release it.
* Touch screen is much easier to use with a stylus, but there is no slot for the 'lipstick shape' stylus in the device!
==UPDATE 5/11/07 13:08==
Resolved a couple of issues.
* Web browsing with Opera Mini 3 is a much faster and better experience than the built in browser, recommended! (no landscape mode though)
* I tried accessing my email through its webmail interface (not talking about gmail here) and it does work very well in the phone browser, so I now can access my mail and use the qwerty keyboard to write replys phew. Might be keeping the phone!