I am using the Ghost hosted platform. They support custom domains and I wanted to use my root domain (eduardobautista.com) instead of a subdomain (www.eduardobautista.com). Ghost advises against doing this but I was not sure why; they are not that clear about the reason.
So despite their warning, I went ahead and did it anyway. That’s how I found out that when you add a CNAME record on the root domain, it will no longer use your dns records. I found out about this when I was expecting an email and it never arrived (I use MX records on my domain because I use Google apps).
So that is why my blog is located at www.eduardobautista.com instead of just eduardobautista.com.
Update: I am no longer using Ghost and have switched to Jekyll, but this is still useful for anyone that might run into the same problem. Update #2: I switched back to Ghost. They now offer a desktop app which I believe is awesome. Update #3 (2017-04-17): I switched back to Jekyll. A static site handles heavy loads with ease. Update #4 (2019-01-11): I switched to Hakyll for the faster compile time.
Update #5 (2020-06-08): I switched to Gatsby because I gave in to our TypeScript overlords.