SF Signal has a wonderful new post up titled "Who Are Tomorrow's Big Genre Stars?" Read through the collection of comments to find the responses from various editors, commentators, and established writers like Gardner Dozois, Matthew Cheney, and Niall Harrison. For those too lazy to read through all those words, here's the summary of up and coming writers, as compiled by SF Signal from the number of mentions in the discussion:

The Top 21 Genre Authors To Keep an Eye On

Paolo Bacigalupi (5 mentions)
Darryl Gregory (5)
Jay Lake (4 mentions)
David Moles (4)
Benjamin Rosenbaum (4)
Cory Doctorow (3 mentions)
Ted Kosmatka (3)
Chris Roberson (3)
Vandana Singh (3)
Daniel Abraham (2 mentions)
Laird Barron (2)
Elizabeth Bear (2)
Alan DeNiro (2)
Alex Irvine (2)
Paul Melko (2)
Naomi Novik (2)
Tim Pratt (2)
M. Rickert (2)
Jason Stoddard (2)
Karen Traviss (2)
Scott Westerfeld (2)

It's worth noting that one of my favorite new writers, Tobias Buckell, was not named anywhere in this. His response to that: "Ouch."