Yeah I think a lot of people around here would be surprised by how infrequently some of us upgrade. I'm still running a 2600 AXP (on my primary desktop), and have no intention of upgrading until sometime in mid 2008.
I upgrade every 2.5 years. My Winny 3000+ was purchased in November 2004 and my core 2 in April of 07. Before that, my Tbird 1.0 was purchased January of '02 and Celly BP6 Summer of 99.
I think I'm the exception rather than the rule around here.. Still running a 1.5 year old 6800GT.