Extension season might not be over yet, but if recent history is any indication, we've seen most or all of this spring's extensions. You have to go back to 2008 to find an extension completed in May or June, so there's a chance that Ryan Braun's deal will be the last one of its kind for a few months.
If that's the case, 37 players will have signed extensions since the beginning of the 2010-11 offseason. Exactly one of those players, Ryan Hanigan of the Reds, is a catcher. It's noteworthy, if not downright surprising, that no starting catchers signed extensions when you consider that dependable catching is hard to come by and that teams spent aggressively last winter.
Unlike the 2009-10 offseason, when the Twins extended Joe Mauer, no backstop was an obvious candidate for an extension. Mike Napoli is getting expensive and he doesn't have a reputation as a good defender. Matt Wieters hit just .249/.319/.377 last year, so it's understandable that the Orioles didn't commit to him on a mutliyear deal. And it would have made little sense for the Indians to extend Carlos Santana, who had an operation to repair a damaged knee ligament (his LCL) last August.
Buster Posey was an extension candidate, but there's no rush for the Giants to extend him, since he's under team control through 2016. Perhaps the 2010 NL Rookie of the Year will be in line for a long-term deal after 2011 if he repeats his breakout rookie performance.
Geovany Soto would have been a more traditional candidate for an extension. He hit .280/.393/.497 with 17 homers last year and was arbitration eligible for the first time in his career after the season. Soto is young enough for the Cubs to want him to keep him around (28) and close enough to free agency that they might be thinking about securing his services for an extra season or two (Soto is eligible for free agency after 2013). They didn't agree to terms on a long-term contract and instead signed a one-year, $3MM deal.
Given the circumstances surrounding each extension candidate, it's easier to see why Hanigan was the only backstop to sign long-term. Next year, however, more catchers, including some of the ones above, could sign extensions. Elite catchers don't hit free agency often, so the teams that develop catching may choose to keep it in place long-term by offering promising catchers extensions.