SIFF blogging
It's good to keep up on the latest movie buzz during the film fest just to make sure you're not missing anything totally amazing. Usually you get this by talking to people in the theaters or overhearing snippets of conversations throughout the theater lobbies. You can also find some information in the local papers that do reviews. Full Series passholders also have their own email list which helps to get more information.
One of the best sources for movie info during the fest is through blogging, and there's a ton of SIFF blogging going on right now. Here's what I've found -- If I'm missing anything, please feel free to post/advertise it in the Comments!
Personal SIFF blogs
Greg's cineblog is totally lagging behind as usual this year, but when he gets to updating it the entries are entertaining and thoughtful.
Chris at Film Lovers Are Sick People writes nice morsel reviews of each movie he saw at the fest which are far easier to read than my ramblings. He has recently added an Audience Watch-ish feature as well.
Ken Rudolph sees a bajillion movies each year and has nugget-sized reviews that serve as a great reference, especially since he sees a good handful of SIFF's movies at other fests prior to ours.
One of the Usual Suspects has very nice thorough accounts of the SIFF-going experience, including well written reviews and ratings, ads that were shown, any goodies offered, and percentage of audience in attendance.
Rich also writes nice morsel reviews of SIFF movies. One thing I like about his blog is the listing of past films he rated highly to calibrate your tastes against his -- an important thing when it comes to reading reviews.
I just discovered Jayde's blog and it's got some good review writing on it that's far less formal sounding than mine, which is a good thing.
Andy Spletzer is a SIFF programmer who writes good articles for film.com.
Collective SIFF blogs
The reviews on these blogs have a variety of contributors.
Seattle Metroblogging's SIFF notes
Film.com has some bits about the festival and is actually hosting a handful of SIFF short films to view online (requires RealPlayer).