I'm sure my PC rig is nicer than most on here, and I could have went with a PC for the TV instead of my PS3. But the PS3 is far easier to just fire up and go do what you want, when you want it. No configuring this/that, having a keyboard and mouse to do basic functions. I don't game much and most of the games I do play are not available on PC. Blu-ray is far quicker/easier to fire up on a PS3 than a PC. I can easily stream videos on the PS3, look through pics, and all that other crap, so it does all most users need it to do.
Yes, surfing the web sucks on a PS3 - which is why we have laptops, iPad, and my main PC.