gfretwell,
outbackpower.com They have grid interactive inverters which are fed by 48V battery arrays, which then are charged of course by the PV system. Trace/Xantrex has just come out with some grid interactive ones as well now, but I'm kinda partial to Outback myself. Their reputation for their inverters producing VERY clean power especially for motors/refrigerators is well known when running off grid.
However I will say, when pricing these systems for a few customers, unless they REALLY want that instant UPS style transfer, its hard to beat a backup generator. Not many people want to deal with maintaining the batteries monthly, and replacing them years down the line. They like the idea of having a maintenance free PV system, especially since it is part of their house. And you are gonna have a hard time running your A/C off the inverters in a power outage. With a standby generator, at about a third the cost of a battery/grid interactive system, at least you will be able to run all your loads. And if you dedicate a 250gallon propane tank to it, you could go a pretty long time in a natural disaster.
I install solar in the South California, so if I can be of any help.