Just looking at the numbers I think I'll stick to the Altitude card.
Altitude gives you 1,200 miles for the first $1,000 spent and 1,600 miles for every subsequent $1,000.
This Rewards card gives you 937 miles for every $1,000 spent (and that's already including the 50% bonus for spending over 5k in a calendar year!). And 1,250 miles per $1,000 at your "Fav 5" merchants.
The Rewards card might give some nice bonuses to start off with (lump sum miles, 100% bonus for first 90 days, etc.), but in the long run the Altitude card still rules.