Well, this is finally changing, as the company apparently plans to release web-based calling (i.e., no download needed) in the next few months. Imagine the possibilities -- simple one-click calling to someone else's LinkedIn profile as an example (in fact, LinkedIn is rumored to be one of Skype's first partners in this regard).
Compelling, eh? Absolutely! Novel and innovative? Nyet.
Interestingly, my former little company SightSpeed (acquired by Logitech in late 2008) featured web-based video calling for years -- here is a link touting this ease-of-use from back in the day.
So, just like Skype's late entry into the realm of multi-party video chat, its new move is a bit late in coming. Has that really hurt the company? Well, not so much.