If you're into rooting and flashing, go pick up a Bionic today. There's a great team of Devs already backing the Bionic, and their ROMs seem to fix a lot of issues that the Bionic had right out of the gate. Plus with the leaked .893 files you've got most the annoying problems dealt with (connectivity issues, camera, etc). Add to that the fact that both the Nexus and Razr will probably have a slew of problems at first, just like all smartphones. So it really comes down to: Do you want a phone that's supposed to have it's major problems fixed by around mid-November, or do you want to wait for a new phone that may have worse issues when released and silently curse it for a month or so while the kinks are being worked out?
As to everything else, it comes down to personal preference. Is a removable battery important to you? If so, the Razr is out. What about using SD cards? That rules out the Nexus. The slight jump in clock speed for the Razr/Nexus will barely be noticeable, if at all. And honestly, I like being able to use my phone in direct sunlight...something that the Bionic does astronomically well.
But, that's all just my opinions and beliefs. I dig my Bionic, and nothing slated to release in the next few months Wow's me as much as it did. Mostly because those phones are not doing anything new or revolutionary beyond ICS, and the Bionic will end up getting that.