A great, great series and the one that I credit seeding the idea of me getting into computer animation as a carer--yes, even moreso than those brilliant guys at Pixar. Mainframe Entertainment is also based in Vancouver, so there's probably also a bit of hometown pride going on here too.
The look of the show changes dramatically over its four season run. In the first two seasons the technology was in its infancy and I've been told that in the early shows the characters didn't even cast shadows. The stories were also a little limp but with some highlights--my favourites back then usually involved Hexadecimal.
When I turned on Season 3 though, it blew my mind. The look had just been up'ed exponentially and the fact that Season 3 was one long plot arc made it that much more interesting to watch. Although this season featured many great episodes, my favourite has to be "Firewall"--the James Bond style pre-title sequence alone is both hilarious and beautiful to look at. The shot of young AndrAIa with fire behind her was my desktop wallpaper for a long time.
Be sure to catch the Season 3 and 4 DVDs--definitely worth watching.