Nintendo - Increase production to 2.4 million/month. Get KOEI back on Nintendo (not DW series, think PTO or RoTK). Create a Ninjabread Man Seal of Shovelware to use to scorn companies into not polluting the aisles. Fix the online mess.
Microsoft - Price cuts in Europe/Others. Price cuts in Japan. Aggressively defend any exclusive relationships. Upgrade the XboxLive servers. Two weeks after GTA debuts, drop the price of GTA by $10. Repeat with every other multiplat.
Sony - I agree with NJ5, fire the entire PR department. Use 2 SKU's: 120 GB native BC for $499, 60GB no BC for $399. Start calling in favors with developers for exclusives. If all that fails, duck and cover.