I do think there's a valid point in the warning from Symantec. Think about it. In the past, Firefox was considered more secure. Yet it had quite a small marketshare and thus not too interesting for hackers. Not enough systems to attack. But Firefox has a bigger market-share now and that does mean it's security system will become more important too. If Firefox wants to increase it's marketshare then the security of Firefox must be improved a lot.
Then again, recently Opera became free and it seems to be an interesting alternative. And Netscape is still alive too. And I'm wondering if there are several more good alternatives. Of course, Firefox is pretty good but it's becoming a bigger target now it starts to gain a bigger marketshare.
