On the other hand, it's not 2001 anymore. Perhaps there are other reasons that router sales have stalled? People are putting it off until they have to do a move to IPv6?
Cisco sells way more than just routers these days, perhaps as part of their hedge strategy after 2001. Mostly through acquisitions maybe, but it's still impressive. Examples that come to mind include Linksys (home networking), Scientific Atlanta (cable TV & broadband gear), WebEx, and Tandberg (video conferencing).
Enterprise routers and switches are still Cisco's bread and butter; sales in software and consumer products can hardly be enough to compensate for a downward trend that may only exist because people aren't buying as many CRS boxes.