Hot price?
GW1 Prophecies, Factions and Nightfall were standalone games and priced at $59.99 each, which was/is typical for new games. Eye of the North was the only normal expansion and was priced at $34.99. I would assume that the priced was based on the amount of content offered, since it was rather small.
$49.99 is the typical expansion price, which will be the most HoT will cost. With the lack of content being revealed however, I’d expect to see the $34.99 price tag again, down to $20 minimum (the cost of season 2). I’m assuming that’s why they haven’t revealed a basic price yet – it would confirm how small it is. Alternatively, I wouldn’t be surprised if the expansion is nothing more than a marketing stunt and ends up being sold for $0 as season 3. The living story doesn’t generate press whereas an expansion does.