Peekvid doesn't have any videos on its own servers. All it does is provide an indexing system to videos on the web. The vast majority of these are actually hosted by YouTube.
Viacom (which makes a large number of television programmes) has recently forced YouTube to remove 100,000 videos from its servers because of copyright infringements. It's likely that Peekvid's index still contains these videos in its listings, which will lead to a large number of dead links appearing on Peekvid.
The Peekvid site itself seems to be working fine. (I've just tried it). It's just that many of the videos in its database no longer exist.
Chris