Having 500 4kw systems cuts into harvest revenues as do 10 20kw systems as the equivalent square footage lost to generate 1MWh is an order of magnitude larger.
Also, wind turbines blades in colder climates tend to accumulate ice in the winter and thus are permitted to be located away from populated areas. Some big chunks of ice have been flung hundreds of meters. The larger the blade the further the distance you need to put your structure for safety reasons. These masts shouldn't be put on buildings (vibration) or near populations (ice).
I am attributing larger footprint usage to trying to generate a similar power output given current wind mast technology. 10 wind masts alone don't take up the same space as 10 classic turbines, but the the number of wind masts necessary to generate the equivalent output of 10 classic turbines is greater that 1:1 due to wind swept area per turbine.
That said, their web site makes them out to be idealistic dreamers (I know that sounds judgemental but it is the impression I got from it). If Google were still running the RE<C initiative I'd suggest they put a couple of test units next to the data center at The Dalles (its on the Columbia River and was always windy whenever I visited there). If they can build a 4 - 10kW one and its something you can stick in your backyard, I would expect that they can build a small business out of that to develop the expertise to build the big ones. I worry that if they try to do too much too soon they will become overwhelmed.
[1] Caveat the amount of energy you can pull out of a moving mass of air at STP is finite.