Yeah on iPod Touch it should work fine, but will it activate? Otherwise each time you reboot you have to do the same.. Not sure if the Touch's require activation though?
Anyways, rapidblue is selling UDID slots for whoever wants to give iOS 5 beta a shot! Only 5 dollaSo give him a shout over at iPhoneZA forums
Thanx @fxit_man
Yip, see this link or this link to get your UDID registered so you can use your iPhone/iPad with the iOS 5 beta