> It's pretty clear that Google doesn't know your father
> or your family situation, so their little reminder is
> a lot different that Bob Barker actually showing up at
> your house.
> Also, I don't get this assumption that your GMail is your
> own personal space.
* You may not 'own' it, but that doesn't mean there isn't an expectation of it being a semi-private space. You are leasing the use of your Gmail page from Google at the price of the ads being there. What if your landlord went door-to-door in your apartment complex telling everyone, "Call your father!" When your landlord shows up at your door, you don't know that he's going around to everyone. How would you not see that as personal?
* "Call your father" is a command, which is a lot more personal than "Father's day is coming up, you might want to call your father for free using our service!"
> There are ads on every single page
Do you not own your (purchased or gifted) copy of (e.g.) a newspaper? There are ads on every page.
> Google has a long history of sending out blanketed messages
> (e.g. new Labs features).
Your newspaper analogy is the most inconsistent yet. Of course you own your copy of a newspaper, and of course there are ads. But a newspaper is not your "personal space," and in fact, I'm sure most newspapers had Father's Day ads.