It's probably about an hour and a half before we might be able to see images, but NASA's Phoenix probe has landed in the north polar region of Mars. Touchdown was circa 6:53 Central Daylight Time tonight. NASA has a signal from the spacecraft. Now they're waiting (circa 20 minutes) for the dust from landing to clear, at which point they will direct the lander to begin opening its solar panels to take in power.
This was a huge success, considering that the mission's name reflects the fact that it arose from the ashes of the Mars Polar Lander mission when that probe crashed (or otherwise was rendered inoperable) in December 1998. The Phoenix team had to cannibalize leftover parts and software from the MPL mission and from one other Mars mission that was cancelled. A lot of the instrumentation they had to work with was less than ideal for their mission, which is to explore beneath the Martian surface for traces of ice or water--and signs that there may at some point in the past have been life on Mars.
Come on, Phoenix!
Update: We've got pictures! Here's a mosaic image of the view on the right side of the lander: