Its now possible to use GoToMeeting integration from the Lync 2010 client (since this is client side integration it should also work just fine with Lync Online / Office 365).
To initiate a Meet Now session simply install the latest version of the GoToMeeting client.
Then just right click and choose GoToMeeting
Im not sure of what I think of this yet, its like CUCILync but for meetings, but in general im pro to have options so I guess its good. Like in a scenario where you run Lync fully internally but one particular customer of yours runs their meetings in gotomeeting, well why not use this sort of integration then?
Source: Thanks Ove