Volkswagen approved a limited production by 2010. However, production has been delayed until 2013. The initial price is still unknown.
But it still uses an internal combustion engine, which have a horrible energy efficiency. I wonder how such a bad technology has lasted for so long?
Energy density of the fuel. An electric version of this should be significantly heavier (and I think bulkier) due to the batteries, quite possibly having regenerative breaking wouldn't be enough to get back the losses from the extra weight.