I love the Dread Saurian, but I do have to admit that it's really hard to use just because of the base size. If you're playing on a table with so little terrain that his base size isn't an issue, you're likely having other issues because that just means that your opponent is probably just rushing you and destroying you turn 1.
As for 3rd edition rules, I'm pretty sure that we won't be seeing any warscroll updates, just because it's Forgeworld and they rarely change their warscrolls. I do imagine a massive points hike, though, making him all but unplayable in the new rules.