I absolutely despised Norton previously, this dates back to many years and security suite of sorts (cant remember exactly which one) on a family pc. and always advised strongly against it, to everyone i spoke to about norton. the issues for me were the resource usage, and how difficult it was to get rid off in the early days. i was just given an old toshiba satellite pro to repair for a family friend, and it had norton 2002/3? loaded, and i actually couldnt remove it no matter what i did (symantec tool, safe mode, uninstaller etc) and eventually decided to do a fresh install to avoid bouncing the laptop off the walls.
however ! i was recommended Norton Internet Security 2009 by a friend, with a previous dislike for Norton. i thought it must be worth a try for said friend to be recommending it. to cut a long story short, i love it. they have really sorted out the resource use, it has a high detection rate, and it was also dead easy to remove (something i tried for the hell of it) once you have the settings that is pretty much it, very little intrusion. it also has a couple of neat features - Norton insight, which catalogues all the safe files on your system, so it doesnt need to continuously scan the same files over and over. it also has an idle scan feture, which means that you dont have to run a scan, it does it itself, during its idle time.
i am also running the 360 beta on my laptop, and find it equally as good. anyone that previously hated Norton (of which i was one) i suggest you give it a go, you will be pleasantly surprised