ThreadWatch has a good explanation of what the new Google search is, and what it isn't:

What it is, is feed search. On the surface there's not a greatly noticeable difference for many, but the difference is there, and it's quite profound once you understand why.

Many feed items are truncated, or otherwise edited - just snippets of the complete "on site" post. This of course means that you're not getting the full picture. You're getting a pretty good slice of that picture, but it's not complete, not by a long shot.

So does that give full text feeds an advantage? I would think it does. Given Google's dominance in the search space, this fact all by itself may change the dynamics on full/partial feeds. There's going to be a cross current - people and companies want traffic to come to the site (not least for the ads), thus driving the decision toward partial feed content. On the other hand, here's Google, effectively cutting those sites off at the knees in terms of search rank.

This should make things interesting, to say the least.