As for transparency? Well, it's true that it can't be reproduced well in one certain mediums. Sometimes you need a one color design. It's okay to take advantage of the medium that it's used for, even if it's sacrificing consistency slightly. I've seen style manuals with several variations on logos and its possible to have a transparent compatible version and a one color compatible version. I'm not really afraid when designing for spot color on newsprint. It often pays off to try things that other people say won't work.
Still, it's not just about being trendy. So apply these ideas with both inspiration and restraint. It's still about expressing visual information. Not only that, but logos can sometimes stay around for a very long time. So I wouldn't recommend something that could easily become dated. Unless it was for a time specific event maybe. I also don't think that making intelligent use of the trends would make them dated either. Logo 101 is so web 1.0.