Ok so let's get this started off by looking at some key Avacyn spoilers. At the end of each post I will give a projected price range as well as some further speculation regarding pricing.
This is definetley a card you want to get your hands on. It has a very wide range of uses that some people may not consider. Its 3 colorless mana cost makes it versatile for several deck types. It can abuse the enter the battlefield abilities of several creatures such as any of the 6 titans or possibly cards like Rune-Scarred Demon or Massacre Wurm.
Initial Projected Price Range: $6-$8
Notes: The true test for this card will be the Avacyn Pro Tour and I think that it will do well because of its versatility. Expect a price increase within a month after the launch of AVR. Get them while you can.
-Kevin