If Nintendo decides to keep the current Wii on the market with it's successor, it could gradually surpass the PS2, a guess from me at least.

I want it to, but it's still at least two years -maybe three- away from doing that.

I don't think it will, it will get close though. None of the consoles of this gen will have a lifespan anything like the PS2's, which may very well get an eleven year lifespan or perhaps even twelve even if the hardware numbers will be minuscule by then.
A sprinter and a marathon runner are two different things and I see the Wii as a sprinter to be honest.

Yes but it will take more time.

20 million twice in 2 years?

Not likely.

Depends on when the next Nintendo console is released.

I figured the PS2 would put on another 20M or so on account of the third world markets picking up and the 7M difference between Sony sold/vgchartz sold accounted for with these regions over the next 3 years. 

It's actually only been just over 3 years, or about 40 months. It basically has sold roughly half the PS2's numbers in well under less than half its life. So it should be on pace to outsell it.

I think Wii should easilly have another 3 years of strong sales (maybe another 50-55 million during that time), and probably another 3 years after that of decent sales (20-30 million). It could very well make it to 150-160 million when it's finally stopped selling, provided Nintendo doesn't permaturely cut the lifespan of the Wii short. So I think it will just barely edge out the PS2.

In short, Nintendo has plenty of coconuts.

I think nintendo doesn't care about beating the PS2 and will release a new console when hte wii stops being very profitable (i.e pretty soon if they have to keep cutting the price to maintain sales) also HD penetration is getting larger, Nintendo can probably release a new console soon. so no

I don't know, because I have no idea whether Nintendo are likely to keep selling the Wii after they release Wii2/HD. If Nintendo do with Wii what Sony did with PS2 then it's yes, if they do with Wii what they did with GC then no.

PS2 will probably top out at close to 140 million. So according to the OP's predictions for the Wii that means somewhere in 2014 for Wii's target take over date.

I think if Wii2/HD releases at $250 and is profitable from day 1 it's likely that Wii will fall away very quickly, and Nintendo may well discontinue making/selling it inside a year. PS2 could, did and needed to keep on selling because PS3 was so expensive and PS3 was (is) unprofitable. Ninty's only real motivation for continuing to produce Wii after Wii2/HD is released is to unseat PS2, it's a worthy goal to achieve but only if it makes good business sense. Wii could be like PS1, and Wii2/HD could be the real PS2 killer. If Wii2/HD keeps the Wii momentum going then it could well do 200 million.

I decided to compare the wii and ps2's sells year by year
                                                                                         How much is the system outselling it
2000 PS2                                 2006 Wii                         Lead PS2 2.1 million
5 million                                   2.9 million                          

2001 PS2                                 2007 Wii                           Lead PS2 2.1 million
15.8 million                              15.8 million

2002 PS2                                  2008 Wii                         Lead Wii 5.2 million
20 million                                  27.3 million

2003 PS2                                  2009 Wii                          Lead Wii 8.1 million
18 million                                  20.9 million      

2004 PS2                                  2010 Wii                            Lead wii 13.1 million
15 million                                   20 million(estimate)

2005                                        2011 Wii                                Lead Wii 15.1 million
18 million                                 20 million (estimate)

2006 PS2                                 2012 Wii                           Lead Wii 19.1 million
13 million                                  17 million (estimate) 

2007 PS2                                   2013 Wii                              Lead Wii  23.1 million
10 million                                  14 million (estimate)

2008 PS2                                   2014 Wii                             Lead Wii   22.1 million
8 million                                     7 million  (estimate)

2009 PS2                                   2015 Wii                              Lead Wii   21.1 million
4 million                                     3 million (estimate


As you can see the wii is outselling the PS2 year by year. If wii keeps the pace up. It will have no problem outselling it.