Running latest OSX with a 4 GHz Intel Core i7
Build 3126 ran at 0% resting and 5% when active. It also consumed 256MB of memory when resting & 310MB when active.
Build 3143 runs at 10% resting and 18% when active. It also consumes 815MB of memory when resting and while active.
Both scenarios are not indexing and have the same projects and tabs open.
This feels very un-Sublime-like