I'm a little late to the party on this...
I'm a Glock guy and I currently carry a Glock 23.
That being said, I would recommend the Glock 19...I'm making the switch as soon as I can find someone to buy my 23...lol For me its a question of the cartridge. For the little bit of "stopping power" you gain with the .40, the 9mm will give you more rounds per mag, a cheaper price per round, and significantly less muzzle flip which makes it easier to keep follow up shots on target.
So, yeah...Glock is my #1, but other than Glock, I would have no problems recommending the S&W M&P, Springfield XD, Ruger SR9c, and if price weren't an issue...I'd love a Sig P226. All are reliable and will work well, so it comes down to what you feel more comfortable with...I recommend firing all the guns you are looking at.