Other good choices are (ordered by my most preferred down to least preferred):
http://mandrill.com/http://www.mailgun.com/https://postmarkapp.com/http://sendgrid.com/http://www.jangosmtp.com/With all of these you can use SMTP as interface for outgoing emails, or you can use their API (which might have advantages in some cases).
Mandrill and Mailgun have nice "free tier" that lets you use them for free up to a certain number of emails per month, but you'll probably find (like I did) that the IP addresses they use for the free tier can be blocked a lot due to RBL's. This is becoming a major problem with Amazon SES as well. If you're serious about your email delivery you'll really really want to pay for the unique IP address so you can manage your own email reputation better.