The google mac team have released Google Quick Search Box. Looks like they are edging into the QuickSilver (not not in development anymore) and TaskBar (non-free).
This is interesting because while being an app launcher and app "do stuff with"-er (though doesn't seem quick as cool as launchbar or quicksilver in terms of chaining stuff together), is it is obviously a google search engine, and you can integrate search from your google or twitter accounts.
A bit of testing sees it as having very much potential. Intuitive if you're used to using QS or LB at all, feels a bit laggy compared to QS/LB, but having things like results popping right in (ie: put in "weather
Also according to the reddit article the development is done by the QuickSilver creator, Nicholas Jitkoff.
I'm sold so far....