Here's what I found so far.
As everyone knows by now, it now allows you to choose the QWERTY keyboard in portrait mode.
Ditto with the keys on the landscape keyboard which are now a bit bigger than before.
The charging issue which plagued Ver 88 is now resolved. The phone will charge normally, and the battery seems to hold a charge for longer.
Pressing the lock key now takes (ONLY!) five seconds to lock the phone. Clicking the screen during the locking process doesn't seem to have any effect as it used to in 87 and 88 (in 87 and 88, locking would take about 12 seconds, and clicking the screen will make it immediately lock).
Once locked, clicking the screen won't turn the screen on as in previous OS. This is useful for e.g. when the phone is your pocket, the screen won't turn on accidentally thus saving battery.
The update is now intelligent enough to send you your Service Books, thus saving one step after the upgrade.
The camera now has transparent bars, so you will see the full image while composing and also while the picture is being saved.
One issue: sometimes the camera will NOT save your pic. You'll have to Close then restart Camera and the pic will then be able to be saved again. However, the problem will crop up if your picture taking session is long, so you may have to exit and restart the camera multiple times.
The video also now has the transparent bars so you can see the entire scene. Videos are in 3GP format.
One issue: after taking a vid, and watching it in Media Player, your phone may hang.
Media Player has louder sound now. The Up & Down buttons will raise and lower the volume, not go to Next and Previous as it did in OS 87 and 88.
You cannot fast forward songs, and the slider bar doesn't appear either in landscape or portrait mode.
In videos, you can finally fast forward and rewind the movie, and the control is now quite fine, unlike the gross movements in 87 and 88. The slider bar will only appear in landscape mode.
Browser seems a bit slower, or maybe it's because I have my default as Column view. Changing from Column view to Page view seems a bit quicker than before though.