You are on a T-3 with (i assume) uncapped upload and download speeds. Many users on Gnutella have cable modems. Most cable modem providers allow download speeds much higher than thier upload speeds. If you (T-3) request a file from a cable user, your download speed is limited by the users upload speed. If you upload a file to a cable user, your upload speed is limited by thier download speed which is much higher than the same cable users upload speed. This is why your uploads are faster than your downloads.