They are fairly new yes. And I think the real reason they haven't trended as well is because of the pending cards coming out soon the 8000 series.
Exactly, people are mostly waiting for the 8000 series now which will probably be coming out somewhere around march-april. The new 7870 XTs are great cards, especially the sapphire version which offers great cooling. If you really need a card now, go for it, or you can hang on a few months and check the 8000 series. I've seen the 8870' specs, and I have to say, it sounds like a winner.