@Groucho: I wasn't talking about do the 3rd parties think Wii is worth developing for. I was addressing your post, when you said, that Nintendo was addressing 3rd parties with the graph. Because they aren't.
3rd parties don't think Wii is unattractive, atleast if we look at upcoming titles, which tells us that 3rd parties are profiting from Wii.
About porting, that's where you're wrong. Saying that "downporting" is easier than "upporting", is the same as saying that PS360 games can be ported to Wii as they are, but Wii games can't be ported to PS360 as they are. There's a reason why Capcom is remaking Dead Rising for RE4 engine.
Then again, according to you, PS3/360/PC multiplatform titles wouldn't be a problem for Wii, since they are easily ported.
In reality, porting to higher specs is the easiest thing to do, since anything that runs on lower specs, runs on higher too. I'd say that the easiest port to do this current gen, is a Wii to PS3 port. Both uses OpenGL, both has PPC processors, Wiis specs are that much lower in pretty much everything, that you don't need to work around bottlenecks (unlike PS3 360).
If you wan't to reach every platform cheap, you develope your game for Wii, port it to PS3, 360 and PC.
Wii doesn't need 50% marketshare in order to be the most attractive platform, since developement is cheaper. EA has stated that porting can cost (by their metrics) 15% of the original budget in order the port to be seen profitable. If we go by that, one PS360 game costs atleast twice as much as one Wii game, and port would increase the cost by 15%, which would mean that one PS360 multiplatform title should sell 230% of the Wii game sales in order to break even. With PC, that would increase to 260%.
PC userbase is irrelevant to game sales, since PC:s used at work overlap with PC:s used at home and PC:s are primarly bought for other things than gaming (which btw is shown by games attach rate) and with PC:s, you're facing competition from the browser flash games. If the PC installbase would mean something, consoles wouldn't exist, since nobody would be making games for them.
Wiis userbase is less targetable than PS360 userbase, i agree, but you also have bigger chance to have success for the same reason. If your PS360 fails to reach its target audience, you're losing big money. At the moment with PS360 you only have two possibilities: make a game for the targeted userbase, where competition is heavy or target the audience outside the existing, which is unproven. You're going to spend atleast 20 million anyway, so the chances to lose money are high. And in any case, when you look at the proven userbase, you can't discount 1st party sales, since they clearly show what kind of games have sold on the specific platform.
Wiis online marketplace isn't weak, the biggest complain i'd expect from the developers (the biggest ones) is the size limit, which favors small developers.
Online play isn't weak, problem is, that Nintendo doesn't have similar standardized online as PS360 has, it's the same as with PC, although Wiis online is the most accessible. This gives advantages as well as disadvantages (and Wiis online is free). And, unlike you believe, Nintendo has stated they are going to improve it.
Look, so far we have had only a handful of PS360 titles that have turned a good amount of profit, while Wii has had a shitload of them. Maybe they haven't made the same amount of profit than the handful of the PS360 games, but due to faster developement time and cheaper developement, Wii offers faster retuns of investments and lower point to break even.
That was pretty much off topic, but the thing is, that Nintendo doesn't need to tell the publishers how much money they can make with Wii, since they already know it.
@321: The title is Mario&Sonic at the Olympic Games.
