One of my clients recently moved to Google Apps as their full time email solution.
I had my reservations at the time, but more on privacy grounds than technology ones. It turns out there are technology issues as well. My client was very excited about improved spam filtering from Postini. After the move he told me right away that he was getting a lot less spam.
This same client runs an insurance business with online application forms. Those forms go to special unfiltered email boxes. Of course those addresses aren't released publicly.
So they get all their forms and don't have to worry about miscreant insurance filters (most of my other clients are in real estate and we have filtering issues in real estate and mortgages as well).
Over the holidays, we couldn't figure out why Adwords was sometimes claiming more completed applications than the client was receiving. My tests were working. Finally we compared lists.
My client wasn't getting all the completed applications that were going into the database.
It turns out that Google Apps/Mail were deleting quotations (even though they were coming from his own domain).
What's the solution?