Well Guys/Galls I broke down an bought a 28g hqi Nano for Christmas and it has FINALLY arrived! I plan to start the tank with all live sand and Tonga branch live rock...If i use a 50/50 mix of tank water from my 90g after a water change and fresh salt mix will it help my tank cycle any faster? Or should i just start from all fresh mix?

i think you have to start fresh but use some sand and live rock from the first tank to seed the new one

I bet there are some beneficial bacteria in the water column of your old tank, but the sand and rock will provide considerably more. IMO, though I know of no evidence beyond anecdotal to support my opinion, I don't think using 50% old tank water will have a sigificant impact on the length of your cycle. Then again, I can't see how it would hurt.

I would go ahead and use the tank water. Like James said it can't hurt and there could be beneficial stuff in it.