The design - the white,thin body really makes it stand out & it's guaranteed to be picked up by someone for a look if i leave it on a table or something.
It's fast and smooth (commented on by a couple people)
It's capacitative
The screen (one of the girls was oo-ing over it the other night while looking at pics)
The app store grows everyday
It can do everything the iphone can do, but better (i absolutely hate my friends who came from a nokia 3310 and think the iphone is the pinnicle of technology)
Widgets
THE D-PAD! Hugely underated - i've used trackballs before in blackberrys & they can be oversensitive, prone to damage, and kinda creepy. I use the D-pad all the time when web browsing to select hyperlinks that are too close together for fingers (like this site for one). It's also v handy for quick and accurate cursur placement for texts.
Also i'd just like to take the time to mention a couple games which i think are v good:
-robo defense
-gogo rescue squad
-mechanics
-retrodefense
-labyrinth
-brain genius
-neocore(for showing off)
-mystique(supposedly - but i havent figured out how to move forwards in it!)
I only have one complaint (i know no negativity allowed, but i dont think this counts as negativity, just a minor annoyance) - is the dedicated keylock button. If there was the option to make that redundant the galaxy wud pretty much be the perfect phone.