Having a wireless connection should have no bearing on wether or not you can connect or download from the iTunes store. I've experienced issues with iTunes for months, and have always gotten the same line of BS from Apple with regard to the slowness - - that it's my wireless connection, or that it's my router, or that it's my ISP, or it's some setting in my browser, or it's some unsubstantiated problem with my Mac/PC/i-whatever. The one thing I have noticed is that slowness/outages from iTunes are more likely to happen on weekends as their servers become overloaded. Hopefully, issues with iTunes should improve when the NC data center comes on line -- but I wouldn't count on it being better for long.
As for Apple: they need to learn to acknowledge problems when they occur. In this respect they are worse than Microsoft.