I had a similar thing happen to me. In my case, I was still able to boot into hboot. I'm not sure if you're able to as well, but if you are, keep reading.
Here's what I did:
1. With my phone connected to the computer, while in hboot, I flashed back to the stock recovery using fastboot and adb.
(If done correctly, this should leave your phone with a triangle and red exclamation mark.)
2. I had to flash back to a custom recovery (I use CWM)
3. I flashed a custom rom.
This wipes all of your data, but at least you get your phone working again. Maybe if you still have the backup saved on your card, you can load it up in recovery once it's been reinstalled. Also, I'm assuming that since you rooted your phone in the first place, you can find the stock recovery on your own.
I hope that helps.