Upgraded to Feisty, but can't start it - not the at-spi bug

[Krister Ekstrom]

Hello folks.
A couple days ago i upgraded from Edgy to Feisty, yes it's a little
early, but i wanted to see how the new feisty looks. Well, as more or
less expected Feistys gnome wouldn't start, i got the Gdm login screen
but after typing name and password, nothing happened and after hitting
enter once more i was back at the login prompt again. I thought it was
the at-spi bug mentioned here on the list and so i waited a couple days
for some upgrade to come. Today though i had a sighted guy look at my
screen while logging in and it turns out that what happens is that after
typing username and password, there pops up a big empty window with a
smaller empty window in it. No text, it's just empty.
This leads me to believe that something got broken during the Feisty
dist-upgrade. Is there a way to reinstall the whole Feisty distro via
apt-get? As i don't know what could've gone wrong and Feisty claims it
has Gnome and everything installed, i don't know what to do here other
than reinstall.
Thanks for any help.
/Krister