Naughty dog co-president  Evan Wells has revealed on his Twitter account that uncharted 2 demo is getting closer:

“The most important deadline so far on Uncharted 2 is right around the corner!”

"So close now... I think we might actually have a pretty sane weekend (knock on wood!)"

http://twitter.com/evan_wells

Update: although it's not confirmed, E3 may be the date to reveal a playable demo of the game. 

oooooo... when? a demo this summer would be fantastic!

That would be awesome. I played the Uncharted one demo like crazy when I first got my PS3.

I'm looking forward to this!

Uncharted is one of the rare PS3 games that got me excited so far.
With Uncharted 2, that will make a total of 4:

Uncharted
Flower
Metal Gear Solid 4
Uncharted 2


CAN'T WAIT FOR THE DEMO!
Uncharted 2 baby!

can't wait to unchart the demo myself...

it comes out what like november or something

i made this too!!pity it was after this!!

Demo as in E3 demo or demo as in PSN demo?

^

I'm guessing E3 booth. I wouldn't expect a demo until November (unfortunately; this game looks awesome!)