My problem, is for my pages that I host for hobby on my domains is another $5USD for every domain I currently had 10, add that to hosting, and domain names themselves, and 50 bucks more is not a option for me, specially as I'm not using advertising, and as DH could pay for a expensive cert (wild card) for all their mail.dreamhost.com, also I'm of the same idea of DH that a self signed cert in this case is equally secure , I have create and sign my certs for more than a decade, and that these are real certs too .
My second problem is on my work, as a teacher I'm not the owner of the college sub domain where three of my machines live, so this way the only solution is to buy a wild card cert and I'm not totally sure as probably they will need some more work and authentication.
My totally personal solution, has been like in the old days, on the road use mutt on whatever terminal I had on hand via ssh, and at home use full Thunderbird, I'm not that friend of portable apps and running on every machine, I don't trust is not my first choice, not to say unsecured networks and so.
Anyway thanks for taking a moment to read, I hope google add some real option to this mess. I'm in no way understand how this is going to secure and avoid spam, as for sending they accept self signed certs to comply with mail RFC. Well it's going to be interesting for all schools and colleges that don't care about this and won't be willing to pay for a thing that worked for more than twenty years. The main problem is now hosted mail and payed solutions that integrate pop/ssl from older systems my work place buyed that solution to filtrate spam with gmail and receive mail on their own servers, Monday afternoon lot of users are going to be calling support about the warning on failed to retrieve pop.