iPad 2 is expected to be announced soon, & available within a few months (going by Apple's track record & its love of annual product cycles).
Quick re-cap of some of the competition's specs in 2011:
[Released Sep. 2010] Samsung Galaxy Tab - Android 2.2 (Froyo), 1GHz ARM Cortex-A8 CPU, PowerVR SGX 540 GPU*, 512MB RAM, front & rear cameras, 7" screen.
[Upcoming] BlackBerry PlayBook - BlackBerry Tablet OS, 1GHz ARM Cortex-A9 dual-core CPU, 1GB RAM, front & rear cameras, 7" screen.
[Upcoming] Motorolla Xoom - Android 3.0 (Honeycomb), 1GHz NVIDIA Tegra 2 [ARM Cortex-A9 dual-core CPU plus GeForce ULP GPU*], 1GB RAM, front & rear cameras, 10.1" screen.
While the current iPad has: 1GHz Apple A4 [ARM Cortex-A8 CPU plus PowerVR SGX 535 GPU*], 256MB RAM, 9.7" screen
*[GeForce ULP used in the Xoom > SGX540 used in the Galaxy Tab > SGX535 used in the iPad & iPhone 4]
Most rumours agree on a slimmer design for the iPad 2, along with front & rear cameras.
More RAM for the iPad 2 is surely a given. 256MB RAM really is quite low now, against last year's Galaxy Tab (512MB) & definitely against this year's newcomers (e.g. 1GB in the PlayBook & the Xoom).
Also, when you look at the competition, it would make sense for the iPad 2 to also have a better CPU & maybe also GPU. The current 1GHz Cortex-A8 plus an SGX535 is already a slightly lower spec. than the Galaxy Tab has (1GHz Cortex-A8 plus an SGX540), & definitely lower than the PlayBook (1GHz dual-core Cortex-A9) and Xoom (1GHz dual-core Cortex-A9 plus a GeForce ULP).
Some iPad 2 rumours so far...
Digg's Kevin Rose - iPad 2 to be announced by early Feb, higher resolution, front & rear cameras
Reuters - higher resolution, front & rear cameras, slimmer & lighter
iOnApple - smaller bezel, wide range speaker, flat back
Analyst Ashok Kumar via CNET - 1GHz ARM Cortex-A9 dual-core CPU for the iPad2