As confirmed by @MuscleNerd via Twitter, developers looking to jailbreak iOS 5 Beta 3 (released today) can do so with redsn0w using the same version released a few weeks ago.

MuscleNerd notes:

Today’s 5.0b3 can be jailbroken with last month’s redsn0w http://is.gd/6eek4Y(point it at 5.0b1 IPSW..devs only please!)

As long as you still have the iOS 5 Beta 1 firmware file, you’re good to go!

Thanks MuscleNerd and the entire iPhone Dev Team for their hard work!