Assumptions should be revisited after a while. Jakob Nielsen eased the pressure on frames last year. Lately I’ve seen some clever uses of them. Bipolar has permalinks within frames, while Newsblogger and Blogger have nifty frame interfaces. Some sites such as Gamers.com or Hoovers use a frame that sits on top of outside sites. Bad if there’s no way to remove the frame, but otherwise it might be useful to build a sense of place and direction for newbies. It’s also a way to keep useful features at hand, such as a search engine or a site rating system.
Overall, it seems frames are more adapted to application and grocery sites than to content. My point is, let’s not stick to religious opinions on design and remain open to different, sometimes successful implementations of infamous technologies (OK, it’s harder with Flash!)