I just recently bought the 2011 MacBook air 13" base model. My trackpad isn't nearly as sensitive to touch as all the store models I've tried. For example, when i use two finger scrolling it doesn't detect both fingers but about half of the time unless I put more pressure on the trackpad. The store models I've tried takes far less pressure to operate correctly. The same goes for three and four finger swipes. This is my first Mac so I'm not sure if maybe its a newer version of lion (I'm not sure what version the store models were running) or if it's my Air. Has anybody else seen this problem? maybe there's a setting I can't find?