Impressive, and I like the speed. Not sure
suggestions are my cup-o-tea, though this seems it could be handy if I used them more heavily. And you should probably watch the tab order / arrow keys, sometimes it seems to get lost, and can "select" entries which are not visible. I'd probably capture the tab key in JS and control it manually, otherwise my settings let tab go to
every link + form item.
I'd probably get more use from something like this which searches my history + bookmarks + delicious + instapaper + etc, and does a normal search on those. Otherwise, currently, I type in "xcode" and get 3 from my bookmarks (missing my "xcode plugin" bookmark, among others), and none from my history, despite having 19 xcode hits in my history.