Why switch outgoing ports?
Some ISP block port 25 for their users. It's an attempt to cut down on the possibility of sending spam out - if you have to send it through their servers, they can monitir and control it. Dreamhost has enabeled port 587, which gets around this block.
I wouldn't worry much about your E-mail being intercepted. I don't see how this is a possibility anyways. Dreamhost E-mail is sent throgh secure connections... it's no easy business getting that stuff. There was an issue that came up before, that this statement may have stemed from. When you send out an E-mail from DH servers, they first check with their own DNS to see if there's an entry for that domain, if there is, it's sent there. If there's no entry, they do a look up for the name servers, and forward as appropiate.
Normaly this is just fine, but it's percievable that someone adds a domain through the panel that they don't own - now they will get all of the E-mail dreamhost customers send to that domain. I believe Dreamhost has some safegaurds against just any old domain being added, but it's a possibility (a very, very small one)
I think I'll go update see about updating the wiki article to be a little more realistic.
Perhaps one draw back to having the knowledge base in the wiki is that you can no longer see what Dreamhost officially has said, and what is user commantary. I wouldn't pay any attention to that entire part.
You're always welcome to post questions on the forums, regardless if they're presnet with every host or not. The only thing most people ask is that you (and I'm not saying that you didn't) search before you post. If it's been asked before you can find your answer quicker with a search than asking all over again. So by all means, post away. (it's late)