It is when PSN is essentially providing the same basic service (online play) as XBL but charges Nada. Add similar Marketplaces to buy full games, exclusive arcade games, and rent and buy (only on PSN) movies, it gets harder and harder to justify the price that Microsoft charges for XBL.
Especially when online play on the PC, PS3, and Wii are free, paying to play online games on XBOX Live is pretty crappy. It seems more like a measure to help the bottom line, rather than charging for a premium service, especially since Silver XBL members can also download movies, games, and such, all going gold gets you is the ability to play games online. I'd argue a point that the money spent to make people go online is less than the money paid to the numerous studios, Netflix and the like for their content.
With MS getting 50 dollars a person and there being 12 million (gold + silver live subscribers) that's six hundred million dollars a year, again, minus silver members. Since there aren't any real conclusions we can draw of the amount of gold-silver ratio, but let's just assume that only 50 percent of gamers who have XBL accounts are gold. that's 300 million they make for services that are free on every other platform. That's a pretty big deal.
