With Android Google stepped into a mature market for the first time and appears to have committed rookie errors - it's not the stuff in the Nortel or Novell portfolios which is generating income for Microsoft - and a lot of Microsoft's patents were created through old fashioned in-house R&D - exactly the sort of innovation which should be protected.
<cynical_speculation>It may have been in Google's interest to turn Andorid into Open Source in October of 2008 due to the liability incurred when Microsoft acquired Danger's patent portfolio earlier in the year. Particularly in light of Google's antipatent corporate culture and Andy Rubin's role in creating Google's phone software.</cynical_speculation>
Only if that "innovation" is actually novel, non-obvious, specific, and useful, and certainly not for 20 years (roughly 13 generations in tech years).
It may have been in Google's interest to turn Andorid into Open Source in October of 2008 due to the liability incurred when Microsoft acquired Danger's patent portfolio earlier in the year.
If Android was always based on the Linux kernel, then they probably had an open source plan from the beginning.
Edit: With Android Google stepped into a mature market for the first time and appears to have committed rookie errors
This sounds like code for "Google stepped into our territory and didn't pay its protection money."
Frankly, it should be ok to enter the market the way Google did.