On their website:
Maybe they're hoping they will be more successful if they follow the trend and use "+" in their name. 
Just in time for this premier:
I’ve heard they’re also raising the price by $2.
If anybody cares ( ), I got an email today and the change will happen on September 10th.
Also in the email, they mention that the price increases to $79.99/year (up from $59.99/year now) or $7.99/month (up from $5.99/month now).
So you are correct, that's indeed an increase of $2/month.