Don't know if it will pass Wii, but the emerging markets will help. I'm in Brazil and can tell you that no one here wants a Wii. It is considered obsolete here, you only see PS3 and 360 in stores. Websites e-mail offers don't come with nothing about the Wii anymore, so it could give PS3 a shot at that mark.
In this kind of market, a PS4 launch won't change anything. PS3 only started selling really 2 years ago here, when the price became better. In emerging markets, PS3 legs will surpass PS2 simply because PS3 is more expensive than PS2 was in the same time frame. A PS3 costs US$ 500~600 here and that is too expensive. The PS2 cost was around US$ 350~400 in 2005 and the piracy made it a more affordable alternative than PS3 is today (new games cost US$85~100, older titles are around US$40~50). 360 will sell well here for long too. I predict that PS4/720 won't be relevant in emerging markets until 2016 (with a 2013 launch). PS360 sales will probably increase here by a healthy margin in the next 3 years.
Comparing shipments it with PS2, PS2 have 104 million units in 2006 (http://vgsales.wikia.com/wiki/PlayStation_2) and PS3 will probably have somethinh around 75~77 around March. So PS3 is having roughly 75% of PS2 shipments. Calculating by an aproximated 150 million PS2 lifetime sales, we have 112 millions for PS2, what looks even a good prediction because PS3 may have longer legs because of the higher price point when comparing it with PS2 at the same time.
