They'll do slave mode, so if you put the SB910 in slave the firing of the SB600 (which you seem to have covered) should fire the SB910.
That said, I use Vello Freewave Fusion controllers, which will double as a remote camera trigger if you wire them up backwards (flash unit on the camera and trigger unit in your hand). No TTL, but otherwise perfect and reliable. Get a second receiver if you're not using slave mode.
Do you know if I can trigger both speedlights with the built-in flash?
My understanding is that both the D7000 and d300 will trigger one flash (I can confirm tonight) – but I assume this would work for more than one?
My fear is that back when I was using the d70 this didn't always seem to work as expected. However, that was a long time ago ...
So the lights worked great ...
during set-up.
But had some major issues throughout the night =[
I had so many things go wrong last night during this shoot and I'm still not sure what on of them was. There was a point at which I sent a line of people back to the dance area because I needed to figure out what was wrong. Then there was the time i called my wife to bring my backup "always on" light from home -- then there was the girl that tripped over its cord and broke the giant CFL light - thank God the girl didn't get hurt or cut.
I ended up getting everyone photographed but I have a GIANT shadow behind many of the shots the because my daughter was holding the (attached) speedlight in my backup setup.
I actually offered them a discount but they refused.
Lots of retouching ahead for me but we may eventually have a few somewhat satisfied customers ;)
