A big hearty welcome back to everybody’s favorite feathered Rube Goldberg engines of destruction and their slingshot in Angry Birds Rio. Amazon.com has just opened an alternative marketplace for Android apps with their very own app store and it’s doing insanely well. In fact, Angry Birds, Angry Birds Seasons, and Angry Birds Rio have already slingshot themselves into the top-five paid apps mere hours after the unveiling of the store itself.

Today, March 22^nd, Angry Birds Rio is a free download—so you have about 12 hours left to cash in if you want it. Just sign into the Amazon app store and download it. After this initial release promotion it will go back to $0.99 a pop.

For those looking to try before they buy, reviews of the game have already started cropping up and it’s a finely-preened-fowl indeed. Eli Hodapp has come out with a review raving about the upgrade to the Angry Birds franchise at Touch Arcade,

Angry Birds Rio basically plays the same way, but the entire game feels like it has been upgraded. Quite a bit of the interface has been redone, there are far more things to collect, and they’ve even added parallax scrolling to give the game quite a bit more visual depth. The 60 included levels are all designed incredibly well, and seem to have solutions where you can brute force the level by destroying it, or looking for the single weak spot which sets off a Rube Goldberg-like chain reaction of destruction.

Instead of killing pigs, you’ve got to break fellow birds free from cages in the first world. Then in the second world you’re defeating monkeys. The 60th level has a boss fight of sorts where you’ve got to fling birds at Nigel, the bad guy of the movie. You even get to fling Blu and Jewel, the two main character birds of Rio. It’s all really well done, and any fans of Angry Birds will have a fantastic time playing through Angry Birds Rio.

Of course, Angry Birds Rio is an expansion in the Angry Birds line based on the animated bird adventure that presenting in theatres soon starring George Lopez and Anne Hathaway as voice actors. The IP from the movie is used liberally throughout the game and it’s basically a sort of co-branding that plays off both the popularity of the game and the movie—and, of course, he fact that the movie is about a domesticated macaw who has trouble flying.

The introduction of sophisticated interface development, new design like the parallax scrolling, and other enhancements really show where Angry Birds can go when they come to market with an actual sequel. Still, sixty new levels for only $0.99 will be a hard price point to miss.

Angry Birds recently hit 30M downloads on Android, they’ve been announced for Windows Phone 7, and these ornery ornithopters continue to dominate the charts with little end in sight. Although, from the calendar, it may be a few months yet before the next installment hits the shelves indications that it’ll be solid and delighting seem pretty solid.

EA is probably wishing now they also acquired Rovio (the developer) as well as Chillingo way-back-when. I would be.