It depends on personal experience per individual. Out of the thousands of cases of failed 360 consoles, there are plenty who didn't even get a new console back, or even their original one repaired, but instead another refurbished one that also broke a few days/weeks later. Some people are on their 4th or 5th console, and there are message forums with numerous similar experiences. You've never heard of that with Sony consoles. Does this mean Sony console owners are any smarter than MS console owners? Highly doubtful. I do credit Microsoft with the 3 year warranty but they pretty much had to do that to save face in the industry. I think they learned their lesson on hardware design, hopefully. I'm interested to see what their next system will be like.
As for online, Sony's service is still free, and thanks to their first party games having game-specific dedicated servers, they are also largely lag-free. Resistance 2 will support 60 player multiplayer. I'll agree that split screen gaming is going downhill but I for one have never liked split screen gaming. You can however still sit down with six other people bringing their own controllers and play together on one console, but how many times does this happen in reality? That's like $350 dollars worth of controllers gathered in one place. Almost like a LAN party for consolers. Party games and sports games make sense there but split screen gaming is annoying for most these days, which is why you'll see Halo parties with people bringing their own tv's. Those are a hardcore breed of gamer though.
The Wii....I'll agree that it's fun for a while but even developers are questioning the long term feasibility of it with respect to content. Sure they have Wii-fit, and it's found a great niche, especially with rehabilitation for hospital patients, but for gamers, the idea is sort of a wash. People play videogames to play videogames. If they want to do something active, then go out and really do something active.
Their next console will be one to watch out for, but first we'll have to see how long the appeal of the Wii lasts.