Simply put: Spin off the ideas, but retain ownership, or invest in others ideas. Possibly integrate if successful.
What Media Companies Need to Learn From Startups — Tech News and Analysis
“It’s not enough to simply acquire companies and hope that they will somehow magically make you more innovative or competitive (this is a problem that Google suffers from as well, as many of its acquisitions have shown)”
How true. Take Jaiku as an example, and Google’s attempts at social network services in general.