I played multiplayer on some random servers with stereo3D yesterday and did surprisingly well, though there's a couple of disadvantages to playing this way:
1. Enemies popping up on a different focal plane to the one you happen to be looking take a good fraction longer to register. I suppose an advantage from better depth perception could be better estimation of projectile drop from the grenade launcher or rockets; will have to test more to find out if that's really the case.
2. Input lag and general performance. You have to use vsync to get stereo. Playing last night it was definitely noticable but not debilitating. I'd actually forgot to apply the tweak to render ahead zero frames instead of the default, so that could claw back a bit of responsiveness too. Have to say though, that BF3 seems to handle input lag pretty well when enabling vsync.
Repi
To readdress what I said earlier about the default convergence setting. It's actually very very good. The setting gives a realistic feel to the 3D, as in the characters and environment look to be life-sized. If there could only
be one setting, this should be it. Ideally though, the user would be allowed to play with this. Because we (I) don't have wall sized monitors it's often nicer to make the scene appear to be quite small - like the monitor is a window to an aquarium or dolls house, where you can more clearly see the difference in distance between the objects. The ability to disable the crosshair would finally make my experience complete.
Hey it's Christmas soon, so I'm just getting my santa list sorted. You released the game on my birthday, so I'm sure you're happy sorting Christmas out for me too, I've been a good boy.
/edit Found a setting in the config file GstRender.StereoConvergence 1.000000 - tried a bunch of different values and didn't notice any difference. GstRender.Stereoscopy is set to 0 though, and with no in game option for stereo, I'm gussing these vars are no longer in use.
I've noticed that there appears to be a depth multiplier in effect (hidden from the user) whose value is mission dependent. For example the jet mission has a very low depth setting. The nVidia depth adjustment works, as in it changes the strength of the 3D, but on 100% it looked more like a regular game at 15%.
I'll be very interested to read the blog about the choices made with stereo - seems a lot more hands on than most implementations.