Multi-touch surfaces are becoming increasingly popular. An assumed benefit is that they can facilitate collaborative interactions in co-located groups. In particular, being able to see another's physical actions can enhance awareness, which in turn can support fluid interaction and coordination. However, there is a paucity of empirical evidence or measures to support these claims. We present an analysis of different aspects of awareness in an empirical study that compared two kinds of input: multi-touch and multiple mice. For our analysis, a set of awareness indices was derived from the CSCW and HCI literatures, which measures both the presence and absence of awareness in colocated settings. Our findings indicate higher levels of awareness for the multi-touch condition accompanied by significantly more actions that interfere with each other. A subsequent qualitative analysis shows that the interactions in this condition were more fluid and that interference was quickly resolved. ...