Well, I don't have it yet so I cannot comment on the actual performance.

But the CPU is a 600Mhz Via, and I know Via bought the old Cyrix CPU cores from NatSemi, so I'm hoping it will be very similar (if not identical) to the Cyrix Geode cores. My OpenBrick box here has a 300Mhz Geode, and performance as a server is not limited by it's CPU (but it is limited by the slow rtl8139C network interface and the slow SDRAM interface).

With the 6000CL board, the CPU is double the Mhz, and the memory is 3-4X the bandwidth, so performance should be at least double that of the OpenBrick, which will be way more than adequate for my needs.

The Netwinder it replaces is a 275Mhz StrongArm CPU, with a very efficient (and very buggy) Tulip network interface. I think it's CPU is likely equivalent to about a 400Mhz Geode core, but again, the memory bandwidth ain't that great on the Netwinder. Depsite that, the Newinder is great here, but lacks a third NIC and the means to add one.

Power consumption ought to be very similar between the Netwinder (advertised at 15W, 20-25W more likely), and the 6000CL system (calculated at about 17-20W steady state).

EDIT: And yes, I use (only) Linux for these. The server runs a huge list of stuff for me (everything, basically): sendmail (in/out, plus reflector for some small lists), POP3, fetchmail, apache (4 virtual hosts, plus my geocaching WAP portal), SMB master, firewall/router, DNS master/caching, SSH, ftp/rlogin/telnet/vnc (inside only), vtund (switching to OpenVPN on new setup).

Cheers