The issue is that it's a point-and-click game. Point-and-click games usually fail on consoles because the controls are more suited for a PC.
That opinion has been outdated for a while now. If games like Half Life 2 (FPS) and Command and Conquer 3 (RTS), two games from genres long believed to be implayable with a controller, can sell well on the Xbox, surely it's not so hard to get past the "Genre X won't work without a mouse!" paradigm.
Amanita Design, I'm not sure if you're developing Machinarium in Flash like the Samorosts, but if you're using any C-based language it should be easy to port to XNA, Microsoft's Xbox Open Development Platform.
Something like Machinarium would rock Xbox Live Arcade; so many of us Xbox users are getting tired of the "fast-food" games that inhabit the platform.
Check out XNA, Amanita DesignGo play Syberia on the Xbox, Myst on the PSP, or any other point-and-click game that's been ported to a console, then come back here and tell me that Machinarium will work on consoles. I'm not talking about FPS's or RTS's here. You may say that RTS's have a similar control style to point-and-click adventures, but they really don't. In an RTS, you know exactly where you want to click. So on a console, it's not that difficult to use the analog stick to direct the cursor to where you want it to go. However, with point-and-click adventures, you don't really know ahead of time where you want to click. You keep moving the cursor around to various objects and seeing which one is the correct one to click. With a mouse, this isn't a big deal since it moves pretty quickly, but it's still very precise. But with an analog stick, the developers have to balance precision with speed. Most of the time, they determine that precision is more important than speed, so they make the cursor move slowly. Like I said before, this is fine with RTS's since you know ahead of time where you want to click, but with a point-and-click adventure, that slow-moving cursor can be absolute hell.
Note: This obviously doesn't effect the Wii. I do think a Wii version would be pretty cool.
Note 2: Syberia's controls were actually adapted to a console controller in the Xbox port. The analog stick moved the character instead of using a cursor. There were still lots of control issues because of the fact that the game was originally designed as a point-and-click game, so many of the puzzles became obscenely difficult with the new control-scheme.
