Microsoft: Pretty cool show, but I'm still not that interested in buying an XBOX.
Nintendo: Lightyears better than last year, but still not as good as I hoped for. However, I'm very excited for the new Metroid, New Super Mario Bros Wii, and Mario Galaxy 2. Would have been nice to see more Zelda:Spirit Tracks. Final Fantasy Crystal Chronicles:Crystal Bearers looks to have some potential. DSi - Yes, I'll be getting one.
Sony: Impressive show. Easily the best of the big three. This will be the year I buy a PSP. Without a doubt, it will be the PSP Go, come October time. With FFXIII coming out in 2010, I'll probably hold off on buying a PS3 until then. I can always catch up with MGS4 then.