to fix this, I just ran update manager:
that installed 60 more packages, removed a couple dozen, and ran some scripts.
aptitude install update-manager
after the reboot, the intrepid kernel was running, and my encrypted LVM2 partitions were working. no X though.
first i tried installing nvidia-glx-177:
upon trying to start X, I got the message that my video card was no longer supported in /var/log/Xorg.0.log. then I tried to fall back to older versions. with 173 I also got the unsupported message. with 96, I get an error about unresolved symbols. I will probably spend more time later to try to get that working (probably just need to install another package or two).
aptitude install nvidia-glx-177
to get X to run, I went ahead and switched to the Free nv driver.
then I edited /etc/X11/xorg.conf, and changed
aptitude install xserver-xorg-video-nv
and now X is running, and I seem to have a working intrepid install.