Nicole28: *Raises hand* The account tab vanished for me upon entry into the forums.
However, just like many here, the account tab is normally accessible when you click on GOG.com, by which you are brought to the main website.
It mostly just affects the Community section (including the Wishlists); the store parts of the site (front page, product pages, account pages themselves) still show the Account tab as normal. This is how it usually works when this occasionally happens. :)
EDIT: Closed parenthesis, saving us all
(Interestingly, GOGMix pages also suffer from this bug. I have no idea if that's because they're more closely related to the Community section than to the store, or if it's just because that section is so dated and so poorly integrated into the rest of the site overall.)