I'm skeptical kids. Every few months someone says something like "It could happen," or "I'd be willing," and poker fans get all excited.
The budget for "Rounders" was $12 million. Considering the current rates for Matt Damon and Edward Norton alone, there is no way the film could be made today for such a modest budget, or even twice that amount. For example: The budget for "Lucky You" was $55 million (it made $8 million).
Rounders" did make money, around $22 million. Hardly the blockbuster revenue needed to encourage a studio to green light a project.
Finally, "Rounders" is a cult film, they rarely get sequels, and the ones that are made are generally pretty poor.
Anything can happen, but I doubt that "Rounders 2" will.
Cheers!