GLBSE has been having these issues since v2.0 launch and the Google OTP has just made it worst, as I usually need to type my OTP two or more times before it works and make sure I type it as soon as it recycles to a new one. Then you get to the re-captcha screen which is even more of a pain in the ass.
Unfortunately i'm a small time investor so I'm selling all of my GLBSE assets and buggering the hell out. Mining is moving downwards (at least for the next few months 'til we have a more clear picture with ASICs and stuff), GLBSE is not capable of scaling all that gracefully so I've decided to buy a used old netbook, install Ubuntu and Armory, liquidate all of my assets, including my GPUs and workstations, put all my coins in that laptop and wait it out.
Yea I'm probably going to lose some potential profit in the process but better safe than sorry.
This is exactly why I advised to use HOTP and not TOTP in the beginning. It's just a monumental pain in the ass... please add an HOTP option in addition to TOPT if you are unwilling to ditch TOPT completely.