The Nokia N900 has received the PR1.1.1 software update, which brings the device software to version 3.2010.02-8. Users can download the update to their devices (OTA) over-the-air, but the update is being released in stages, so it may be awhile before it arrives on your device.
Unfortunately Nokia hasn't released a change-log for this update at this time. However since it will likely offer bug fixes and performance improvements it it highly recommended that you install the update.