Ah got it. I thought there would be some API where the transcripts could be searched across videos. Maybe that requires way to many resources for Google to index
Yeah, Google is of course the king of search, so they could certainly decide to revamp YouTube search to include spoken word/transcription matches. They have all the data required to make that happen. That would make VideoMentions Search irrelevant– and I'd be okay with that!
In the meantime, I think this is a useful tool for quickly locating videos based on spoken words.