In the recent past, looking upon the changes that 4E will implement, of most concern for me is that they are adding a load of strange and unfamiliar races to the game core, without any real reason to do so other than to mix-it-up a little and take a break from the norm.
Well, frankly, Im a creature of habit and "if it's not broken, dont fix it" is generally my mentality. 3.5E was/is somewhat broken, and what Paizo as a company at large has added to the gaming experience (item cards, maps, great campaign modules, combat pad, etc) has been a breath of fresh air to a long time DM and a sytem that needed a jump start.
THAT BEING SAID, this may be a personal issue from my experience, but going through the ages, a recurring want, need, dream of players is to to play the drow! So, currently and in the past, I have added drow into the game as a PC class. I see and hear about so many others having done the same. I cant ever remember having had anyone Ive ever played with or myself for that matter wish they could play a dragonborn or tiefling character.
The big initial pull for 4E for me was that they were adding the Drow as a core class.......jee, that just made sense, it just seems to fit, drow have been there from the beginning and in essence are a dark version of the ever popular elf we all know and love. The other more drastic changes that wizards has made to 4E really turned me off, like everyone just getting healing bursts or action points to spend during gameplay to re-roll and such.
My hat (if I wore one) goes off to Paizo for the job that wizards should have done, and they are doing it very well, however, I dont think that I would be speaking for a minority who would say, bring in the Drow! We all know em, we all love em, most of us either have or wished we could play em. Bring em on, its a natural response to gamer need and long time dreaming, and a competetive edge with what 4E folks are doing. GO Paizo!