Zipcar continues its attack on Europe by purchasing a car sharing startup in Austria to extend its reach beyond London and Barcelona, where it has made similar acquisitions. Europeans are generally very open to sharing and with high gas prices and expensive cars there, the economics of car sharing make a lot of sense to your average consumer in Europe. For Zipcar, it’s clear that the company is going to have spend to get into the European market since there are more car sharing companies there where the trend has been around for longer. Zipcar CEO Scott Griffith also told GigaOM’s Katie Fehrenbacher that Asia is on the “medium term” horizon as a future expansion point. What does this all say about the U.S. market? It’s hard to read the tea leaves, but I think we’d all accept that once you’ve gone beyond New York, D.C., and San Francisco, the most promising future markets for car sharing may well be outside the U.S.