I truly hate to be the bearer of bad news ... but:
There is no jailbreak for iOS 4.3.4 for the iPad2. And, according to various twitter posts (and blog posts ... and various web articles), don't expect one soon, if at all. As far as I can tell, the tethered jailbreak for iOS 4.3.4 (for the iPad1 only) was more of a nose-thumbing to Apple than anything else. iOS 4.3.4 was just to close the hole found and exploited by c0mex - it adds nothing extra. So, to jailbreak would be a waste of their time, I would guess...
Of course, all the above is my reasoned opinion based on what I've read - you may reach a different conclusion.
The gist is: No jailbreak for iPad2s with an iOS higher than 4.3.3 at this time.
But still, enjoy your iPad! It's not "useless" just because you can't jailbreak it. Oh, but do keep up hope for iOS 5 coming this fall - I have faith in the jail breaking community. We'll see, yeah?