It's not surprising. Lots of today's top U.S. MMA stars have an amateur wrestling background (Jackson, Ortiz, Liddell, Couture, Coleman, etc.)
I've been a fan of MMA for a few years. But I think you're asking which rasslers are into it. Taker seems to follow it quite a bit, and is usually in the audience for a UFC show.
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A bunch of the MMA guys are also wrestling fans so they're often hanging out at the shows as well. Tito Ortiz has been to a lot of shows including Mania last year in Seattle.
Just by the way Quinton Jackson cuts promos in PRIDE, it'd be hard for him NOT to be a pro wrestling fan.