The FISA bill granting immunity to telecom companies is starting to to remind me of the Kyl-Lieberman bill, a piece of legislation that shows what you are really thinking.  In the case of Kyl-Lieberman it was pretty obvious if you voted for it you wanted a war with Iran.  In fact one presidential candidate had a chance to show she wasn't a war monger by voting against it and she dropped the ball.  Now I can think of a another presidential candidate who says he is different and this bill gives him a chance to prove it.
At this point I don't see the political downside of voting against the FISA bill.  Of course the right-wing will say you are "soft on terror" but they are going to say that anyone and it would be pretty easy to respond "no, I am hard on the constitution" OK maybe that is not the perfect response but you can see where I am going with this, unless you really want to give the phone companies for immunity for eavesdropping on phone conversations, voting for this bill is a bad idea.
In the case of the FISA bill it is pretty clear that if you vote for it you really don't care about the the 4th amendment.   Hopefully, a certain presidential candidate will see it the same way and vote against the telecom immunity bill, maybe even explain why the constition is more important than any information that can be gained by abandoning it.  This goes for torture and many other un-american things Bush and Co have done in the "war on Terror" which really should be called the "war on America by Bush and his cronies to make lots of money for corporations while screwing over US citizens"
Obama says he is different now is a great chance to prove it.