Tapes are just a little more convenient than a reel-to-reel, but sacrifice sound quality. The medium is just too limited... because portability and space saving was the overriding factor. I don't get why it's making a little comeback, if only because of nostalgia and fascination. There are some high end cassette decks that are fetching top dollar now... whereas 10 years ago, you couldn't give them away.
Unlike vinyl, I think the recent cassette tape fascination will fade off. Cassettes were more than just portable -- they afforded customizing music play! The "MIX TAPE" was the big thing. But now? You can burn CD's. You can create MP3 playlists. The cassette tape doesn't bring anything good to the table. The LINEAR progression through the audio tracks is painful. At least with vinyl you can easily skip over a track that does not interest you.
I have to admit, I almost got sucked into vintage tapes. I participate on a forum called Audio Karma, and there are some major tape heads there. They wax on about how you can get a cassette tape to sound nearly like vinyl quality, if you've got a good quality tape and a top notch deck in which to play it. Yes... but that cassette tape isn't going to last very long with repeated play. The thin, fragile tape is prone to becoming uneven and damaged, sacrificing sound quality. Plus, you NEVER get rid of the hiss completely.
I still have a cassette deck, only because I've got plenty of tapes still lying around that I might want to play once in a while for nostalgia. But otherwise, I'm done with the media. In fact, I may at some point just transfer any audio recordings on tape that I want to preserve, then ditch the whole thing.