I could be wrong, but I think that Nintendo's launch strategy with the 3DS may be an indicator that Nintendo doesn't want to announce a system too long before they release it; and with their next home console Nintendo may deny its existance until it is 3 to 6 months away from launch.
Hypothetically speaking, suppose what would happen if 6 weeks before E3 Nintendo announced their next system with a teaser video (like the 'Revolution' Teaser from TGS 2005), at E3 they ended up having it fully playable with several games from all third party publishers that were all near completion, and released the system 6 weeks to 3 months later? In many ways, if you could get third party publishers on board with this strategy you could dominate the news cycle leading up to the console's launch; and maximize the impact of marketing money spent.
Why do I bring this up? Because it is entirely possible that Nintendo could release a system in 2011 or 2012 and would deny it up until they announce their next system.
