No release date doesn't mean anything.

Release dates months in advance are never accurate anyway.

Betas for a game don't necessarily have to last 6 months. The only reason the beta would last this long is if the game is bug ridden.
Long betas don't mean a game is bug ridden. Often it just means they are being through and want everything to be as polished as possible. That doesn't imply that it was horribly broken to begin with.