As a Mario fan, I'm actually disappointed by the "Paper Mario: Sticker Star" game, for a number of reasons:
-They made the battling in the game hopelessly irrelevant. There is no reason to battle anymore except maybe for money. But you use money to buy stickers, which you use to battle more. See the problem? Also, battling no longer gives you experience points, and the game has no level-ups anymore. So enemy battles are merely obstacles on your way to get to the end of a stage or on your way to a boss battle.
-There are no new characters in the game, and there are no partners for you to team up with. Even the lukewarm Super Paper Mario for Wii did a better job, introducing a world of new characters and stories (the best PM game is still The Thousand-Year Door for Gamecube). The reason for the lack of any truly new characters (except for that sticker crown thing that follows you around) is outlined below.
-Shigeru Miyamoto should not be allowed to have a say on the plot or plot usage in these specific Mario games. He came into the office of the development team at Intelligent Systems and saw what they were doing with the PP:SS and basically said something along the lines of "Do we HAVE to have a plot?"
Paper Mario Vs. Shigeru MiyamotoLesser Story, Change in Atmosphere - Miyamoto's input on Paper Mario: Sticker StarThere is a lot of evidence that suggests that the latest Paper Mario was geared to be more of a Super Mario game, than something properly in the Paper Mario series, a series known for story elements and RPG romps. PP:SS seems more like a 3D platformer with some useless battling thrown in, and an absolutely throw-away plot.
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As for what games I recommend:
-PushMo
-CrashMo (both of these are cheap at the eShop and are awesome entries)
-Professor Layton and the Miracle Mask
-Mario Tennis Open
-Kid Icarus: Uprising (AWESOME voice-acting and music holy crap!)
-Super Street Fighter IV (If you don't have the console versions)
-Tales of the Abyss
Retro-new games:
-3D Classics: Kirby's Adventure
(wish there were more, though Xevious is OK and I got Excitebike for free I think)