The FAQ (https://dev.twitter.com/docs/tweet-button/faq) suggests that the tweet button counter will only increment if the HEAD request is successful. Here is the result of a HEAD request to the URL that I am tweeting. Will the 301 prevent my counter from incrementing?
bporter@bporter:~$ curl -I http://reviews.testcustomer.bazaarvoice.com/bvstaging/50test/Product1/reviews.htm
HTTP/1.1 301 Moved Permanently
Content-Type: text/html; charset=UTF-8
Cache-Control: no-cache, no-store
Expires: Fri, 14 Oct 2011 19:24:30 GMT
Date: Fri, 14 Oct 2011 19:24:30 GMT