The criticisms of the deal I have heard from some in the Jewish, pro-Israel right, are chilling. As my mom said in response to those criticisms, “Even if you can't agree it's the right choice, it's an impossible choice. How do you criticize an impossible choice?”
I recommend that reading this piece from Haaretz (Israeli newspaper). I’m quoting a piece of it, but the whole thing is well worth the read:
The deal to bring Gilad Shalit back to his family is painful to Israelis bereaved by terror. It is, by any measure, chillingly dangerous.
And it was the right thing to do.
[…]
The deal for Gilad Shalit is a remnant of a promised land that – to those everyday people who donate their very youth, their very lives, in order to defend it – still believes it important to keep its promises.
The first of those promises is a simple one. When they draft you and process you and inoculate you and arm you and begin to use you, they spell it out, to you and your family both: If you are lost on the field of battle, we will get you back. Whatever it takes.
Whatever it takes. Even if it takes much too much.
The list of the terrorists being released is unendurable. The numbers are beyond understanding. Until you consider that this is how it's always been.
[…]
And this is what I too have said several times today. That no matter what you believe as to the wisdom of the deal, you should be able to rejoice that Gilad Shalit is back with his family. That it is not a new precedent (Israel has been making these kinds of impossible exchanges for decades). And that it was the right thing to do.