i have the same problem how you fixed it
Check the post above yours. He said...
nevermind. i fixed it. since it was flashed over the stock 3.2 rom all of the userdata was still there. a hard wipe did the trick.
So I think you just need to do the same. Do a hardwhipe/soft-reset of the device to whipe the HC user data so ICS can load it's defaults and get you booted up.
P.S. I am still on HC so this info is just based on what I have read so far. I will be upgrading this weekend, unless something unexpected happens that doesn't allow me the time. I think you can do a soft-reset from recovery by toggling the volume in the oposite direction you do for a hard-reset. At least that is what I was told by a support guy a while back. The soft-reset will just whipe user, system, app configuration data, but leaves the firmware in place. the hard-reset will upgrade the firmware(ROM). I think the issue is ICS it's compatible with some of the HC config info and the Update process doesn't automaticly whipe user settings or somthing. *shrug*
