Irrelevant as the GOP seems right now, they'll be back looking for blood in two years, and after Obama's job in four. If history is any indicator, their relevance at either of those points is likely to be higher than it is now. The party in power has a tendency to be held responsible for hard economic times whether or not the responsibility lies with them.
And of course opposing everything the majority puts out is the quickest way to lay the groundwork for this sort of comeback. You can almost hear the arguments now, "that stimulus bill was nothing but pork, of course it didn't work, we told you so." And with every Republican member of the House voting against it they'll be able to make their case.
What I didn't see coming was Michael Steele winning the chairman of the RNC. One of the few African-Americans in the Republican party to have success running for office (though in a blue state), he's pro-choice (he describes himself as pro-life, but believes Rove vs. Wade should stand), supports affirmative action, and is a proponent of renewable energy.
He's not for gay marriage but previous comments seem to imply that he'd rather avoid the issue altogether, and scenes such as those found at Palin rallies of late October are much less likely with a black man at the helm (though revolt from the Southern Strategy branch of the GOP could be a problem). Thus, though he's not going to start stealing Democratic voters away, he will make the Republican party quite a bit less "scary" to voters in the middle.
Since the bulk of the job will consist of refuting President Obama on TV, and there were only two African-Americans running for the position, there were not many sensible options for the party best known most recently for it's old, angry, white men. Still, it seems like the smartest move the Republicans have made in years. Maybe it's just a fluke, or maybe the party is serious about remaking itself.
There is a new man in charge of running their Grand Ole Party, if he is able to moderate the party's base I would expect it to expand and win some seats back in 2010. If not, well, he can't do any more harm.