No one here can really tell you what to do. Speaking as someone who has a bionic i can say this thing fast an has great batterylife. All i really care about , you may want different things. All i can say is samsung is notoriously bad on battery life an they're making the Nexus. Also no phones have concrete release dates.
Not knowing the OP, this is a tough question to answer. But, if he is at all a phone or tech geek, it is bad advice to tell him to burn his upgrade on the Bionic.
I was just in his situation. I had an upgrade in hand, and since VZW has the 14 tryout period, I decided to give the Bionic an honest shot.
After having for ~10 days, I really tried to talk myself into keeping it, to avoid the minor hassle of shipping it back. But, despite the fact that the Bionic is a decent device, ultimately I had to send it back. Because I am a bit of a phone/tech geek.
Yes, there are always newer better phones just "around the corner". But in this instance, just around the corner appears to be REALLY soon. As in the next few weeks. And the reported difference between Bionic and Nexus (and the other devices) appears to very notable.
The combination of how quickly these new devices are supposed to be dropping, how cutting edge they are reported to be, the fact that Nexus is going to have Ice Cream Sandwich, and the very poor execution of several features of the Bionic are mostly what did it for me.
If the Bionic had a screen that had even a little bit of "wow" factor, and if the Bionics camera was not absolutely horrendous, I may have decided to just stick with the Bionic until my next upgrade.
Power/specs wise I dont think the Nexus is going to be light years ahead of Bionic, but it is ahead. Size wise they are similar, but there is more screen real estate apparently on the Nexus. They are both pretty similar in these regards. But.
I am a big fan of high tech screens and this to me, is the biggest difference. Every time I looked at my Bionic, I was reminded that my phone had a very mediocre screen. Only upside was viewing it outside. In every other regard, it was disappointing. I am coming from an HTC Incredible and am used to AMOLED and its rich colors. The Bionic really disappointed here.
And the Nexus screen by all accounts is going to be outstanding. I cant wait to see Super Amoled Plus HD. That is huge to me. A cutting edge device is supposed to wow you with its screen and I expect the Nexus to do just that.
Also, I have a Nikon DSLR for when I must have great photos. This is fairly rare. So, a cell phone with a decent, quick and easy point and shoot camera built in is very nice, because then you always have a camera/camcorder on your person. This is part of what makes them smart phones as opposed to cell phones. I dont need DSLR quality and am quite happy with the results I get from my 2+ year old HTC Incredible camera. This is the biggest flaw in the Bionic, IMO. I would have been perfectly satisfied with mediocre, but current mediocre technology in this phone. Not only was it not current, it was not even mediocre. The Incredible camera was superior in all regards. You can pull it from your pocket, unlock the phone, touch the camera icon on the screen and snap a really good picture in about 3-4 seconds. With the Bionic, you simply cannot. Focusing is a nightmare, and very slow. Then, after finally getting a shot you can live with, it is very grainy and noisy. I cannot imagine how poor it would look if blown up on a 20" computer monitor.
Between that and the pedestrian-at-best screen, I knew I would have a ton of buyers remorse with the Bionic, especially with such great devices this close to being released. But to be honest, even if there were no Nexus or Razor or Vigor or whatever right around the corner, I still would have sent the Bionic back, because after using it for a little over a week, I realized that overall, device vs device, I would rather have my Incredible straight up over the Bionic.
That is why I think the OP, if he has any interest in having a cutting edge device, or EVER uses the camera on his smart phone, would be very prudent to wait a couple weeks and see what drops between now and the end of November.
Good luck OP, you have some great options.