Why don't you get the best of both worlds?
Buy an Apple, and then use Bootcamp to run your Windows applications on it.
The Apple will give you tight integration with iTunes, iPod and iPad and the iPhone, but of course it is more expensive and won't have a lot of the goodies the Sony will have.
If it's any help to you, my grandson bought himself a 21-inch iMac for its looks and reliability, but within a matter of weeks used my old Windows Vista disc to install Windows under Bootcamp because, in his words......."I miss the flexibility that Windows gives me."