Other people have already mentioned on the list memory/cpu isn't
an issue on this day and age. You definitly don't need a c12k to
carry a full routing table today.
This is not what vendors are saying. I presented just after Jeff Doyle
from Juniper 3 weeks ago and he was very specific about this. I
extracted that one slide here:
http://arneill-py.sacramento.ca.us/ipv6mh/j.ppt
Let's face it: I'm sure that Juniper would love to keep selling big
routers. They are telling us they can't guarantee they will keep up
increasing memory and CPU, so we do have an issue with memory/cpu.
Other vendors are saying different things.