Userland Jailbreak for iPhone 4 and iOS4 and 4.01 - Legal under DMCA Now too!
The jailbreak is finally here!
Comex's userland jailbreak and the return of jailbreakme.com, point your mobile safari to jailbreakme.com and slide to jailbreak.
For those having issues, see Jailbreak iPhone 4, 3GS, 3G on iOS 4 / 4.0.1 and iPad on iOS 3.2.1 with JailbreakMe 2.0 | Redmond Pie
for further details.
Since people dont seem to follow the news
EFF Wins New Legal Protections for Video Artists, Cell Phone Jailbreakers, and Unlockers | Electronic Frontier Foundation
Jailbreaking is LEGAL in the US and exempt from the DMCA now
Comex appears to have put an updated version of the site up, to possibly fix iPad 3.2.1, this also appears to may have fixed the issue of iPhone 4 users not getting the downloading dialog after the slide (It did for me)
Mirror site for the jailbreak jailbreakme.modmyi.com