re: 5 Ways Google Should Expand Google+
On the Google Apps side, I can't vouch for other people but personally would like separate work and personal streams to some extent. It's already so hard to disconnect from work, the last thing I want is a notification from my boss when I'm on a social network for personal reasons.
On gmail integration, I guess it wouldn't harm me if it was there as a view in my mail interface, but I doubt I'd use it that much. I'm trying to stay away from email in general.
I'm with you 110% on the Sites integration.
Overall good article.