Of course, a few rumors hardly mean that Perry has decided to run, and if he does run I'm certainly not declaring him a certain winner; I just think, as I've said for a while, that he has a chance to win.
On the original point, however, one thing I could add: running for three years with little publicly to show for it (which is the case for all serious candidates at this stage of the campaign, regardless of how well things are going) is a perfect recipe for seeming boring. They have to trudge through Iowa and New Hampshire, and attend various party shindigs in Washington and elsewhere, giving the same speech over and over and over again. I guarantee: if Ryan, Christie, Daniels and Perry had been running for a year and Tim Pawlenty and Mitt Romney had passed on the race, we would be seeing lots of speculation about whether Pawlenty and the Mittster would enter now and save the GOP from a boring, unimpressive field. In other words, the speculation has nothing to do with the current cast of candidates or anything else; it’s just a function of the way the process works.