For a while, there was a rumor going around that Hugh Jackman was bringing The Wolverine into X-Men: First Class for a cameo. While that was shot down (but still a possibility if they are indeed keeping it a surprise), producer Bryan Singer, director of the first two X-Men outings, has confirmed that there is a strong possibility Hugh Jackman will reprise his role as Logan in a future follow-up to X-Men: First Class.
This is what Bryan Singer had to say on the matter.
"I think there would definitely be room. I think it would be a very exciting thing. This universe has to establish itself first, but that would be a very interesting and fun thing."
"It's a completely different film. Xavier and Magneto are important characters as well. It's just a different X-Men film. I obviously love the character, but you can't not do it just because he's not in it."