litek: The issues with missing account login/my account on front page are caused by the amount of traffic we've been experiencing.
Also, for the future, please include browser (and version) you're using when experiencing a bug - it makes tracking it much easier.
Caused by heavy traffic? Well, I've noticed it for the last 2 or 3 days and only noticed the heavy traffic causing slowdown today after the conference finished. Also, it was only affecting the bar on the homepage and I had no other issues so I didn't think it was browser based. I'd have sent in a support request if nobody else had been experiencing it and I would have included my browser there (I'm using IE9).
Anyway, when I loaded up the homepage a moment ago the My Account button was present again, though the site is indeed very slow with the heavy traffic. Hope GOG's servers can cope as I'm here pretty much every evening.
EDIT: Returned to homepage again and the My Account is gone from the top bar once more, but back to Community and it's returned. It really only seems to be affecting the bar on the homepage.