I just read over on The Handheld Blog that PR1.3 for the Nokia N900 is rolling out across different regions right now. This will bring the firmware up to v20.2010.36-2 and is available over the air. I don’t have my N900 with me at the moment so I cannot confirm if it is available in the US yet, but will try when I get home tonight.
I understand the new firmware has some bug fixes, stability improvements, and support for Nokia’s Ovi Suite. It is also supposed to aid developers in dual booting their devices into MeeGo. It is doubtful that any MeeGo hardware will be coming out this year so this should give enterprising users the capability to try out MeeGo for themselves on the N900 and it is something I will be looking into on my N900 soon.
After I get my Nokia N900 updated I will look around and see if I can find any other specific updates and if an official changelog is posted I will include that as well.