I had this idea at lunch today and figured I'd share it :) Right now Twitter will shorten URLs by default and use bit.ly.
However, when you receive the content via the API (stream, search, etc) you then have to expand the URL by doing a HTTP GET against the bit.ly servers which causes them load and is somewhat redundant. If Twitter were to preserve the original URL on their end, and only return these to 'fat' clients (but keep the original text for phones and existing clients) then you could avoid the HTTP request to the bit.ly servers. Just an idea.... :) Hope it helps. Kevin