Stormrunner
Explorer
Actually, what the Draconomicon says is "...works as the Snatch feat, except you can grab an opponent two or more sizes smaller than you...". It doesn't define "grab" - does it mean you can't grapple a "too large" creature at all, or just that you don't get the auto-damage? IMO it's the latter, since you could always choose to forgo the whole "snatch" bit and just grapple the target normally. It doesn't make sense that taking the feat would suddenly make you unable to grapple anyone unless they're really small. It seems pretty clear to me that what the designers were trying for was "you can grab-and-squeeze any foe small enough for you to pick up in one hand or in your mouth". I do think the prereq should be Improved Grapple rather than Huge size; it gives much of the utility of Improved Grapple, except the +4 bonus, and as written a Large orge, say, couldn't Snatch a Tiny rat.