The Warp Ray has been added to the official site:

http://www.starcraft2.com/features/protoss/index.xml?tab=warpray

I'm a little confused as to what the difference is between this and the colosus. The only things I have been able to pick out are that its an air unit (can't be targeted by ground), and it apprears to be specialized for buildings insted of small units. I guess this is enough to make them different, but the origional game did a great job at making every unit almost complete unique within each race.