I haven't heard anything. I provide a feed of WLAD and the SO. So far I haven't heard anything different as of 1/24/10. I highly doubt they'll move to P25. The system they have in place works flawlessly. I'll keep you updated if they go silent. I also know a few people on the "inside" that will keep their ears open for anything.
Yeah their system is backed by quite a few fixed UHF extenders throughout the county they pretty much have seamless coverage. In an all metal building they might have some trouble, but other than that the coverage is amazing