<p>When configuring the bash on OSX via <code>~/.profile</code> it seems to completely ignore it as soon as <code>~/.bash_profile</code> exists. If this is correct and expected behavior, should I add my extra configuration stuff to <code>~/.bash_profile</code> as well or use it instead of <code>~/.profile</code>?</p>

<p>Thanks in advance.</p>

It's expected behaviour. See
here
When bash is invoked as an interactive
  login shell, or as a non-interactive
  shell with the --login option, it
  first reads and executes commands from
  the file /etc/profile, if that file
  exists. After reading that file, it
  looks for ~/.bash_profile,
  ~/.bash_login, and ~/.profile, in that
  order, and reads and executes commands
  from the first one that exists and is
  readable.
So only the first readable one counts.
As for which you should use, it's up to you - unless there are corporate policies or something else that creates a specific one, or relies on a specific one existing.