I want an advice: i really want to play Wild ARMs 5, but the american version is not released yet. I dont understand a single japanese kanji, but i want to know the game. Is really worth it given a try to the Jap. Version??? Or i wait to the American one???

I wait for the english release during the summer. You should only import a game, if it's likely not going to be translated. I'm a fan of the series, but I can wait. Not to mention importing a brand new game from Japan expensive. You'll spend a lot for the japanese release, then the english release to purchase the same game.

My advice, just get another game(s) to entertain you until it's released.

I'm going to wait for the US version. I'm not in a hurry to play the game.

Since you can't read japanese, you better wait for its US release. Having 2 exact same game but different language is a waste, except if the game offers you something extra or you are some kind of Wild Arms freak, who collects everything branded "Wild Arms". =p

Just like Eva said, get a game to entertain yourself meanwhile. Wild Arms 5 will be released in the US this year so don't worry about it. There are alot of other good games to play.
Also you can ask on this forum or look in older game recommend topics if you don't know what to buy/play.

Get Rogue Galaxy- it comes out next week, and wait for an english release of WA5.

As with most of you guys, I'd also wait til' summer for Wild Arms 5. As it's indeed worth it. If you also got a Wii or PS3, then it's all the more better to forget the Japanese version of WA 5. As with 4, there's bound to be really good acting as well.