It doesn’t happen often, but some version of Angry Birds gets dethroned on Apple’s iPad top apps lists now and then. It wasn’t too surprising when Apple’s own Garageband for iPad took the number 1 sales spot after the iPad 2′s release. However, I was very surprised to see the $1.99 Facebook for iPad with Chat – Pica HD take the #1 spot away from Angry Birds Rio HD over the weekend. Angry Birds pecked its way back to the top spot as we begin the week. But, the Facebook for iPad with Chat app is still hanging on to the #2 spot.

Over on the Top Grossing iPad apps list is what will probably be the seasonal champ for a week or two every spring from now on: TurboTax. The app itself is free. However, the in-app optional purchases are priced between $29.99 and $74.99.

It is interesting to note that presumably new iPad 2 owners continue to buy Apple’s Pages (word processor) and GarageBand apps at $9.99 and $4.99, respectively, in numbers large enough to keep them ahead of the $2.99 Angry Birds HD.