Yes, I still have it. I thought it went away but that was about a day and now it happens again. I'm sure this is much more prevalent than it appears but Apple has a great way of ignoring or denying widespread issues until forced by bad publicity.
Good luck. If I find a resolution I'll be sure to post it here.
Ok, so I've figured out something that seems like the basic issue although I don't know why, this problem of a white screen seems to happen only if the laptop is plugged in overnight while in sleep mode. I didn't understand why it never happened during the day and associated it with the amount of time it was asleep but I think it has something to do with having power to it during sleep.
And maybe that combined with the time issue create the conflict.
Try putting your Mac to sleep manually, do you notice a few minutes where the screen is dark, but the cursor can be moved? This is because your mac is writing the contents of the ram to the hard drive in case it needs to hibernate. The default setting is for the MBP to hibernate after a certain amount of time. The white screen on startup with the progress bar occurs after your mac has hibernated, so the ram has to be reloaded off the hard drive. I'm not sure why your mac doesn't hibernate when not plugged in. I notice that mine won't hibernate if I have an external USB drive plugged in over night and the laptop is plugged in as well.
I'm also not sure why apple made the screen look like it was erroneous, but my sister's new MBP exhibits the same behavior as well. I'm very surprised we haven't have more people commenting on this.
Wait, so is this white screen with the progress bar a normal part of the function of the ram being reloaded? I've waited for quite a while to see if it resolves itself but maybe I've not given it enough time. It looks like it's locked up.
Thanks for the insight into what's going on. I'm totally confused by this.