Just wait until the spyware/virus writers/exploiters catch up with Firefox, which they will. Theres always buffer overflow or other types of holes to exploit in almost any software.
It kind of gives me a chuckle to hear that Firefox is starting to see some actual spyware, which I hadn't known about. I'd love to be vindicated in my opinion that the most exploited software is just the most used software.
Desktop machine: 2 x Opteron 246, Asus K8N-DL, 2GB PC3200 ECC Reg., XFX GeForce 6600GT, 74gb WD Raptor, 2 x 19\" LCDs, Windows XP x64
Server machine: Intel P4 3.0GHz 2MB EM64T, ECS i865pe, 1GB PC3200, 36gb WD Raptor, Windows Server 2003
Laptop: Dell Inspiron 9100 (Intel P4 3.2GHz 1MB Prescott, i865pe, 512MB PC3200, Mobility Radeon 9700, DVD+R/DL Burner), Windows XP
Linux: P3 450Mhz, 386MB ram, Slackware 10.1 (Running mySQL/Apache)