Full disclosure: I have an Xbox, but I only got it (my first one) a few months ago. So I'm getting onboard during the golden age (or perhaps the twilight) of the 360. Reliability and kinks are not a concern.
The "PSN is free" argument is weak IMO. Live Gold breaks down to what, $3/mo? EASILY worth it for the vastly superior of the two services, especially in light of what has happened with PSN over the last couple of months (and still ongoing). Not to be glib, but you get what you pay for. That said, I can understand not wanting to pay if you're primarily using your console for single player and media services like Netflix/Hulu, but if you play online at all, Xbox Live is a no-brainer.
For me, the ridiculous nickle-and-diming we are subjected to as consumers these days is way more rage-inducing. $15 for half a dozen maps? $10 for 30-year old arcade game ports? No dedicated server support? Launch-day DLC that's already on the damn disc? The current state of the video game industry is absolutely appalling. In a busy year, I might buy ~3 games, tops. Most of the last several years I've bought one or none.