I installed Vim 7.3 via MacPorts, and it worked great. However, after I closed Terminal and came back to it, I found out after a little bit that it had reverted to the old 7.2. How do I remove the old, default vim in OSX or force it to use the macports version?
It's probably a problem with your $PATH variable. Check to verify that the vim7.3 install path is in your $PATH variable. If it is make sure it is before the install path for vim7.2.
The vim installer probably set an environment variable for your current shell that isn't in your ~/.profile or ~/.bashrc