I wouldn't really say Live is plug and play, if you are using a wireless network that is.
Like the PS2, I had to manually enter the IP, and all that crap. Took quite a while to get myself online. At least 10 attempts actually.
But, saying that, I never once had to mess with my router or anything, not once.
I didn't have to open ports for it or anything like that as people have said before.
The only mic issue is that most (if not all?) games are open mic. This means everyone is able to talk at the same time, no button to press like on SOCOM. People who played BF2:MC on the PS2 will know what this means. Random people making random comments at random times.
I do like XBL though. I haven't been able to go online for over a week now because my thingy expired, and I cant wait to get back on, if not just because I can play with people off the forum. I have got around 5 people on my friends list from this site, and I haven't played with a single one for more than 2 minutes. (Big Mike)
If you use a wireless connection for the Internet though, you will get a warning saying that certain frequencies may interfere with the wireless controller and visa versa (sp?). I haven't had any problems and I use a wireless, so don't even worry about it.
The 360 is also fat, lazy, English guy friendly. You can even turn the console on and off via the wireless controller. Yes, no getting up.
In theory, the only time you have to get up for the console is if yuo have to put it a new game, or it freezes.
I will tell you this now that in my case at least, all the freezing issues came in the first couple of days of me using the 360. I had about 5 freezes in the first 2 days, and about 5 in the past 2 months. That's less than my PS2 ever had!
The 360 online is absolutely no comparison to any other online service that I have played. It even out performs an online service on computer games which is usually hard to beat. Comparing XBL to PS2 online is almost an insult to XBL.
I once vowed to never buy or even play a 360. I bought one eventually. I will also say that the 360 is the only thing I have ever actually just changed my mind over after looking at a rival product. I got the details of the 360 and the PS3 side-by-side, and my mind was made up.
The 360 is the best console I have played, and nothing even comes close. (Yes I have played the PS3 and Wii, no Im not on crack)