Given Harden's injury history, it seems unlikely that he'll command a multi-year deal, but after missing most of 2006 and 2007, he was able to stick in the rotation for the majority of the 2008 and 2009 seasons, and of course, when healthy, he's got legit #1 starter stuff.
Harden is exactly the type of starting pitcher the Rangers should be looking at, if they are going to target someone. The Jon Garlands of the world, the guys who will take the ball every fifth day and give you 6 innings of mediocre performance, the Rangers don't need. They've got enough options in-house who they can roll with in the rotation that they don't need to bring someone in just to eat innings.
What the Rangers need is someone who gives them the possibility of having a true #1 starter, a guy who would pitch game 1 of a playoff series, and Harden (or Ben Sheets, another possibility), is that type of guy. Are you going to get 30 starts out of Harden? No, probably not. But if you could get 20-25 starts of high level performance from him, like he's done the past couple of years (along with 2004-05), then he offers the Rangers more value than a generic LAIE would.
Harden is, I suspect, someone who won't sign right away...but it is encouraging to see that the Rangers are in on him, because he's the ideal fit for the team, given the Rangers' financial situation and their current player makeup.