I own a SD1 and it is still a great keyboard and can compete with any of the new ones that are coming onto the market. I've heard the KN7000, for me this Technics wasn't an improvement on their last effort which didn't impress me anyway, so that was out of the question. I've only heard the Tyros MP3 demos. It looks nice, has some good styles and sounds (the guitars are good) but it still sounds like a PSR9000 revamped and having to buy a hard drive extra is a bit stingy by Yamaha. The Genesys was the first of the new arrangers I heard and I was so impressed I purchased one 3 weeks ago. The MP3 demos on Gems site do not do this keyboard justice so, I have sent new MP3 demos to a guy on Synthzone who is going to kindly put them up on his site for all to hear. This instrument is easy to use, great sounds and styles, being able to record a song direct to it's CDRW is simple, lovely 32 track sequencer, sampling capabilities, it's worth every penny. It does weigh more than the others, but it's certainly not as heavy as some I've had in the past or people are making it out to be.
It has a large screen which is a nice clear blue colour, not grey and white as mentioned elsewhere too.
Listen to them all and good luck with whatever you purchase.