I've had to restart Boxee now and then for a while now to restore proper performance. The video winds up tearing/stuttering and restarting Boxee clears it up.
I never looked into it much since 9 out of 10 times I could close Boxee from the menu and then restart it with my remote. I do not have a kb/mouse hooked up to my HTPC.
This time around Boxee locked up when trying to exit and wouldn't close normally. When I went to end the task I saw that Boxee was taking up more than 2gb of RAM.
Screenshot of the process list is attached.
Windows 7 64bit, Boxee v0.9.22.13692.
Most of my Boxee use is with local media. The few apps I use with any regularity are Pandora, Netflix, and Weather.