The DS.  The Wii is doing really well, but I don't think the WiiII HD will be nearly as successful unless Nintendo can capture a slice of the hard core gaming market where people are willing to keep upgrading to have the latest and greatest (and even then, I don't see it selling as well -- the Wii phenomenon is fairly rare).  Most casual users will be happy continuing with the Wii.  The GB is a staple in Nintendo's lineup and it looks like it will remain that way.  The Wii is just an excellent bonus.

Of course, if Nintendo comes out with yet another innovation such as stereoscopic 3D game play, that could be another story.

The wii is more important.

Nintendo have ALWAYS OWNED the portable gaming market, GameBoy, GB color, GBA.. and have rarely had a worthy competitor:game gear, NGP color, wonderswan. So it was pretty much a given that the DS would continue the trend.

The wii however has allowed nintendo to rise to the glory as it did in the good ole NES days, with sega and sony supplanted nintendo have little to worry about now.N64 and GC didnt do much to widen nintendo market share, unlike the wii which seems to be getting new customers in for ninty..

DS. If they Wii were to suddenly fail, they would have their beloved handheld as a fallback, much like Sony with the PS2/PS3 situation.

Like many have already said, Nintendo pretty much already had a good grip on the Handheld market. After the dissapointing sales of the Gamecube, and even the N64, in comparison with the PS2 and PS1 respectively, what Nintendo really needed to do was gain some strength back in the Home Console market. Which they have done. They have both the excellent selling hardware, and also the millions of first party software they sell. Wiis success in this generation, should definitely help them in the next. So I'd say the Wii is more important.

This.

DS is definitely more important. Handheld is more important (in the future) than non-handheld, and if they were going to lose one - and dominate one - they would choose the DS.

I too would have to say DS, in the sense of which is more critical to their strategy.

However, if you look at where 1st-party software is going, Wii handily outweighs DS, so i dunno

The DS!

Hell they made me buy one.

it changes, DS was falling in Japan so nitnendo had to focus on that. however wii software is being challenged by 360 so nintendo is putting thiersoftware their

The handheld.