A thing that came to mind regarding Sony and Nintendo jumping into the motion-control business, is that it allows them to have third-party developers who make exclusive Wii games utilizing moion control, to also develop for the PS3 and 360.  However, since the basic opinion of third-party Wii software is that it isn't all that, and not worth the time of anyone. 

Anyone care to comment here?  Is Wii third-party software notable?  And would Natal and Move be effective for getting copies of Wii third-party titles?

oddly enough i think that move and natal might improve the quality of wii 3rd party software. by having 3 platforms to develope a game that is based around motion controls should see more experianced game developers take a shot at motion controls, which in my opinion the primary reason for weak third party support on the wii.

Wii is successful because of first party support. 3rd party motion control developers dont do much to boost the Wii, so i dont see them boosting the 360 and PS3 much either. They'll get a piece of the cake, but it wont do much for sales imo.

So both the Move and Natal will need a strong first party support to be successful, and imo (again) the Move feels like it will come with a strong initial amount of games but drop quite fast. Natal will be more casual and with an already lack of first party, i dont see Natal receiving any more support than the 360 has today.

So in conclusion, both will have very low impact on overall sales, but will receive some action from Wii developers. Move might get more support from 3rd party Wii developers due to similarities with the Wii.