To refer to the OP's question - before you go for a Campag gruppo, definitely check out the spares catalogues (and possibly use last year's one to check the individual parts in the Ergo levers - since like BK says they've grouped the inards into single part numbers for this year rather than selling them as individual parts). If you do, you'll find that the only difference between the new Veloce and Super Record is the 11 speed ratchet and the carbon outer/brake lever. Check through the other parts in the gruppos and you'll find similar cross over. So, where am I going? Unless you're racing top level pro or have the $$ to burn, think about going lower on the gruppos - keeps $$ in the pocket for bits where you'll really see a functional difference from spending more.
I did this setting up my cross bike. I've always run a combination of Record and Chorus on my roadies, but broke with tradition and set up my crosser with Veloce. I was nervous about functionality and going that low on the gruppo "family". I can say after abusing the crap out of it (including dumping the bike on the road at 70km/h during a training ride ...) that it works as well as the Record does. This continuation of the quality across all gruppos is to my mind one of the biggest strengths of Campag compared to Shimano. (Interestingly, SRAM seem to have realised this in their '09/'10 gruppos - at least according to my mate who runs Red on the road and Rival on the cross bike.)
It also means that, given there is stuff all difference between Centaur and Veloce (carbon lever blades and stickers), you can spend something around 105/Tiagra prices and get Ultegra functionality ... I'd actually say better than Ultegra functionality - but that's in part because I'm expecting that the run of problems that people had with new Dura Ace will be replicated in the redesigned Ultegra ... (Sorry to all Shimano fans - but in the few bits of their stuff I've had on my MTB, I've had more problems than with all of my other components on all bikes combined, so yes, I am no fan of Shimano ...)
As for changing over the wheels - definitely the better option, but there are spacer kits and Shimano splined-Campag spaced freewheels out there. For a spacer kit, I got one sent to me from
http://www.wheelworks.co.nz - and ran out the WH-500's that originally came on my cross bike with it. I can't remember the manufacturers who turn out the freewheels ... I think that American Classic and Miche may be two of them - but a good LBS should be able to tell you. That said, it is definitely better to run Campag splined hubs ...
Oh, and to expand on Avanti's comment ... the saying is "While Shimano wears out ... Campag just wears in" ..
🙂