Not that typical in a merger, especially a "growth seeking" merger (like what Google does) vs "cost cutting" merger, like what Oracle does.

This is unusual for Google, for sure. What that tells about them (i.e growth expectations etc) is anyone guess ...

I disagree. I think this is very typical. This is Google's largest acquisition and one of the the few that isn't a startup.

When a company does an acquisition of this size there is bound to be numerous redundancies, specifically in the HR department.

For another example consider EMC and RSA.