Lol, I was gonna start a similar topic, looks like Unseen has saved me the effort.
This follows a discussion we had on MSN on Sunday in which Unseen claimed to have seen a recent survey which concluded that Norton AV was crap and AVG was the dog's.
Now basically I have always used Norton AV / INternet security on all my PCs past and present and while I agree about the system hog thingy (even though I never noticed it on my PCs) I have never experienced any compatibility issues or other problems to note, sure I have downloaded a few trojans over the years and Norton has always got to them before they did any damage and deleted them (until Vista), NIS has always passed all the online firewall tests and AFAIK my system has never been compromised by hackers.
Now I don't think Unseen is an idiot and I know he means well - but his disliking of almost all the most popular of software and hardware have taught me be sceptical of his claims, even though he mends PCs for a living

So at the risk of upsetting him further I did some research of my own using google, and these were the only comprehensive online comparison sites I could find that compare Norton to AVG Pro:
The results are all in different values. some % some marks out of ten etc etc, but the general trend of all the results does indeed contradict the general opinion of Unseen and the other users who have replied here, I could go along with the "eek Norton is crap" sentiment that seems to be based entirely on the fact that it uses more system resources than other AV software, but as I said, I have had no problems with it.
And for the record, I have personally de-infested plenty of PCs with AVG free installed.
So what I am trying to do is separate the shocking facts from the (un)fanboyisms and politics, these are the sites I found:
Website / Result for Norton AV / McAffee / Grisoft AVG Pro / Kaspersky / Bitdefender / Trend / Eset Nod32
Of course I don't necessarily believe these sites are anything more than sponsored advertisements, but the trend does seem to contradict the idea that AVG Pro is any good at all not only compared to Norton but also to the other software, of course these sites are just trying to sell software, but AVG Pro is also for sale

In fact, going off those it seems that Kaspersky is the one to go for, it seems to fair well in the comparisons and is not a system hog, and is not "crap" apparently, and bitdefender doesn't look too bad, a credit to Mug and his great big broadsheet newspaper reading smugness
The main thing that struck me is the lack of any "independent" websites that give plausible evidence to support Unseen's claims, all you get is such comments as "norton is crap".
There are many forums covering this topic, and the general opinion seems to be that Norton is crap, poo, a system hog, that is it

So if it is a hog because it does more to actually protect the system then it is runtime well spent in my opinion

So, until I see some real evidence to support that the claims here are more than just personal opinions based on something other than fact then I will continue to use the best selling anti-virus / firewall, actually I may even change to one of the "better" ones (going off real evidence

) as long as I can get a decent firewall as well - we can talk about firewalls in another topic perhaps.
I'm not disputing that norton is crap, but according to the the most plausible of the vast array of dubious data available to me, it would seem that norton is considerably less crap than AVG.

so there you go.
P.S. Unseen, two of the trojans I found were exes associated with 2 pieces of software that I know you use, I may have even got one of them from you

so you might want to install AV software, will tell you the details on MSN later

(if you are still talking).