I'm Regan, and I live and map in Anchorage. You can gmail me at rsarwas. I've been doing updates mostly in South Anchorage, but I have been straying all across the state. I hope I don't step on your toes. If I do, it was an accident, and I apologize. just drop me a note, so we can coordinate.
There is lots of work to be done in Alaska. Unfortunately, I have not found any areas in Alaska that have Yahoo imagery available, however, we do have lots of other good resources.
The 2009 Tiger Line data is much cleaner than the 2008 data that was used to seed OSM in Alaska. It looks like they spatially adjusted their data to the GPS highway center-lines that were previously available from AkDOT. I haven't tried to replace existing (unedited) tiger data with newer data, if anyone has a scheme for that I would like to know.
Most (all?) of the downloadable data at the Municipality of Anchorage is in the public domain (check the metadata). The metadata requests that the data be attributed to the to MOA GIS department, so use an appropriate source tag.