Mac (9734 programs)

Pros: Makes transfers of all kinds much easier. Easy to setup shortcuts. Allows you to save text snippets for later reading with the URL. Installs packages automatically for you.

Cons: No direct support for other online services, such as Picasa or YouTube.

Pros: Has tons of features, from an IM client to online videos. Well-presented and polished interface. Includes RSS feeds. Widgets expand goober Messenger.

Cons: Interface is a little cluttered. Radio and video channels are obscure. Video, mobile and landline calling not available yet. A lot to pack into what is essentially an IM client. Supported by ads.