Microsoft supports move to open source!
The recent announcement that Yukon would be delayed wasn't really surprising. The reasons given for the delay (make the product more solid, basically) are good. But, the delay has a high cost.
I think the biggest downside of this decision does not accrue to Microsoft, but to the software developers and resellers who support SQL Server's success. It might not be a big deal to Microsoft to delay the ship date a year since they are sitting on $52 billion in cash, but that kind of delay is deadly for small ISVs. I wouldn't be surprised if this delay causes more than a few to take a look at their open source options. This could have long term implications for the future growth of SQL Server.