I stumbled upon a problem with WP 3.4.1 de-de today which might be a bug. At least it has cost me some time to figure out the cause.
When you set up a blank WP 3.4.1 and enter port 80 explicitly in the settings (i.e. "http://localhost:80/yourBlogName" for both WP address and site address), your apache will send the browser into an infinite loop of HTTP 301 redirects for the WP front page (checked with firebug network monitor).
Removing ":80" will restore the usual page load behaviour. I noticed this as I was switching between different ports for an installation under development after having issues in another context.
From what I know, normally it should be no problem to set port 80 - it is optional but ommitting it should not be mandatory.
Anyone with insights as to whether this is intentional?