Let’s keep the discussion technical… Gold membership is a requirement for any internet based service on the xbox because it proxies access to the internet. 8 years ago when XBOX Gold was created it was a defensive measure (this was back when MS was creating Windows XP SP 2 and had massive security problems). Look at the PSN as an indication of what can go wrong with security. The Gold membership fee really covers the cost for these apps to proxy the traffic. You’re not paying for IE, you’re paying for a proxy to the internet.
That said, I hope we see a better network enabled architecture announced for the next gen XBox that doesn’t need such a draconian measure.