It's fine on submission, but it's escaped in Preview and a few other places, such as in Tracked Thread notification emails. I think Lee filed a bug for it, but thankfully it's not a major issue.
-> A few other characters are also affected, including the greater than/less than signs.
John
When I use the & sign in a post body it previews as "&" (no quotes)
http://imageshack.us/f/838/ampersand.jpg/
but, when submitted, is just fine and dandy. No big deal but just didn't want anyone to run out of things to worry about. 
Chowhound
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