3DS: 90 million - 250 million
Nintendo 6: 80 million - 200 million
PSP2: 50 million - 100 million
Xbox3: 40 million - 100 million
PS4: 30 million - 100 million

PS4: 120mil. Sony will have an excellent launch (unlike Ps3), cheaper price (unlike PS3), and it'll be easy to develop for (unlike PS3). Will be out for 8 years before PS5 releases. (if it releases). Won't lose much exclusives to MS because this time, they'll be owned by Sony.

720: (if MS doesn't get more first Party): 70mil. Will sell a little bit better than 360 but will have it's lifespan cut short. Will be out for 6 years before XB4 releases (if XB4 Releases). Won't be able to steal IPs from Sony because Sony will own them.

720: (if MS does get more first Party): 90mil. Will be neck and neck with PS4 in America but weaker in Japan and slightly weaker in EMEAA.

Wii2: 130mil. Not really sure with this one. I'll just assume it'll do good like the wii.

3DS: 150mil:

PSP2: 100mil: Will sell like PSP but won't stop selling due to piracy.

Hrm... I think next gen will be quite similar to this gen. This is what I'm going to guess:

-Wii2: 125 million. I do think Nintendo is going to go with some more power, since that's what a lot of the 3rd party developers wants. It will remain the weakest home console of the gen, but it will be closer to one of the others. My guess is that the Vitality Sensor is being delayed for this.

-Xbox 720: 95 million. Kinect will be included standard with this, giving developers that final push to keep making games for it. (And yes, it will also have a controller.) Watching the fight between themselves and Sony means that I think MS is going to try for a balance of power, price, and market, and actually land it fairly well. Knowing that Nintendo does have a similarly deep pocket, they're not going to go straight out for Nintendo. On the flip-side, I could see them also playing the power race with Sony, knowing that both MS and Sony are going to lose another ton of money doing so. Given Sony's weaker financial shape, MS may try to just push Sony out entirely. That won't, however, be instant, and should MS take this route, subtract 15 million from my guess.

-PS4: 65 million. Fool me once, shame on you. Fool me twice, shame on me. I think Sony is going to keep playing the arms race, pushing as much as they can without actual regard for price. If MS takes my predicted scenario, the PS4 will be undoubtedly the most powerful system. However, it will fall victim to the same problems that plagued the PS3: too high of a launch price, too hard to program for, etc. Except, that with the 720 being closer to the Wii2, it will get less 3rd party support, as the specs on it won't line up with the other systems. Move will be standard, but I don't see it getting as much use as either Kinect or the Wii2's controller. If MS does go the arms race, Sony will have to play things carefully to avoid falling right into MS's trap. I don't know whether they will or not, but since it would be closer now to the 720, the 3rd party games will be on all systems. In addition, I would then add 10 million to the estimated sales to compensate for the tighter battle.

-3DS: 130 million. It's definitely going to explode out of the gate, however, I feel that they will have a harder time getting more people to upgrade from their old DS. Even a new Brain Age game won't get all the converts, however, the increased focus on "hardcore" games will somewhat offset the loss from the lack of converts.

-PSP2: 35 million. Late to the market again versus the PSP vs DS battle, coupled with the sour taste left in some gamers (and developers) mouths means there will be fewer people buying fewer games. This will cause the 3rd parties to abandon the PSP platforms, causing it to die early, and I think will also more signal Sony's exit from traditional portable systems.

I was joking more than serious, as I said, just for fun, but they are the weakest of the big three, we all know Nintendo will be around forever, and MS has money coming out of its pores

Do you really think Sony will make the exact same mistake with PS4 as PS3? I don't think Sony is that dumb.

^They don't have to be that dumb, Nintendo has the advantage going in, and as long as they don;t do something stupid, they are in the driver's seat for next gen, all they have to do is go in with another disruptive innovation

Agreed. I'm not fond of the Wii and I cherish the PS3 but as soon as you gain strong attention of the consumer (like the Wii has from toddlers to grandmas), your reputation grows exponentially and puts you ahead of the other guys. I think Nintendo is going to dominate next-gen with the Wii2, 3DS, and who knows what else. Personally, I still use Sony products as my primary source of entertainment and always will.

Sony, as a company, has shown a desire to want to push newer technology. Unfortunately, this isn't cheap to do. Since Sony is an electronics company moreso than just a gaming company, I believe that they see the Playstation line as a way to further their electronic development and technology. And with Sony's push this season being 3DTVs, I don't see Sony just saying "Oh well" to the the current tepid sales; they're going to want to find another vehicle to push it. Why else would the PS3 be pushing so hard to add it?