dont worry bout the GPS issue, as i read somewhere that there a fix coming, official fix from samsung...Galaxy S should be getting 2.2 sometime this month according to some Samsung official, at least in the UK, IINM...

if you are planning to use your phone for a very long time, then choose Galaxy S...the CPU+GPU is powerful enough for foreseeable future, well at least end of 2011...also the built in 2GB which can be used for apps without rooting...
main thing that put me off is the price RM2599 for non-contract is kinda steep and also the built quality, well at least for me...

in my case, i bought Desire mainly because of Sense features (which like what hTC claimed, more people-centric, rather than concentrating on apps), and i'm totally in love with their People integration with social networks like FB (although again there are some pretty pesky bugs)...

another main factor: planning to get a dual core CPU phone , thus i choose to buy the cheaper alternative....

oh yeah, SGS do have live wallpapers...