Marvel sent over some updated information on Thor #611, which was supposed to be the first issue by the new creative team of Matt Fraction and Pasqual Ferry, but will now be by Kieron Gillen and Rich Elson. The above cover is by Mico Suayan.
No word on whether this is a situation where Gillen needed an extra issue to wrap up his story or if the new team just wasn't quite ready to take the reigns, but either way I think Gillen has done some great work on the title, so I'll look at this as a bonus.
Here's the solicitation info for #611:
Marvel is proud to unveil Mico Suayan’s brand new cover to Thor #611! As Siege concludes, the Marvel Universe embraces the Heroic Age, but rising-star writer Kieron Gillen and artist Rich Elson reveal Loki’s latest machinations as Thor is sent on a dangerous journey…to Hell!
THOR #611Written by KIERON GILLENArt by RICH ELSONCover by MICO SUAYANRated T+ …$3.99FOC—6/3/10, On-Sale—6/23/10
Update: A commenter pointed out that Gillen is also listed as writing issue 612 in the latest Marvel solicitations. I checked in with Marvel, and a spokesperson said, "Stay tuned—we’ve got some exciting news about Matt and Pasqual, but right now we’re all jazzed about the great stuff Kieron has planned!"