I haven't heard anything about Account Scoring since then.
You can do scoring on your own of course. Marketo can't write to the acct object, but you could have SFDC pull the scores for all of the Contacts associated with an Account and then tally them up. Not sure if you'd do an index or an avg or even a weighted avg based on Title.
It would be some sort of formula field in SFDC that would theoretically sum the scores from all contacts attached to the account. I'm yet to sit down and play with it to see what the formula would be though, so it's still just a theory.