I am currently downloading a tv show for Itunes. My network monitor shows 240kb/s in and 4kb/s out. When I stop the in goes down almost to zero, and it seems that pages take less time to load.
Am I right in the conclusion that the download is significantly slowing my browsing?
2.5GHz 13″ MBP 4GB ram Google chrome


It completely depends on what you are downloading. But that seems like the reason.