Amazon Route 53 is a reliable and cost-effective way to route end users to Internet applications.
For my personal domains, I use it to route website traffic to AWS and e-mail traffic to eUKhost.
Route 53 provides aliases but in other DNS servers it may be necessary to use CNAME records:
How can you get Route 53 to point at a mail server which is not on AWS?
How do I set an MX record in Route53 for a GoDaddy domain? on Server Fault
Dns email records godaddy and AWS route53 on Stack Overflow
I am considering eUKhost for my e-mail and AWS for my webservers: