If you look at IDC (as of Q3 of last year), you will see the following in lifetime SERVER shipments:

Itanium: 275,227
Opteron: 4,101,514

That basically says that for the life of both products, Opteron has outsold Itanium by almost 15:1 (and Itanium had a 2 year head start).

I believe what that used might have been total system cost, which is a bit unfair. A $200K HP Superdome probably nets Intel ~$4-8K in silicon revenue (or, ~2-4% of that total system price). If the average 2P server is ~$3500-4000 and average 2P CPU is ~$300-400 in ASP then you have an interesting dilemma.

Would you rather have 2% of the system price on a 275K market or ~10% of the system price on a 4.1M unit market?

If you really want to look at revenue, let's compare silicon revenue on both products, not total server revenue becuase intel only takes home a very narrow sliver of the $5B they were talking about. I'd even bet that the total itanium silicon revenue number is probably lower than the total itanium R&D + manufacturing costs.