I called up my ISP this morning (Shaw.ca Vancouver) complaining not being to uploads or very slow 0.25Kbs uploads speed and they told me they are not blocking P2P but would get a higher rep to call me back, sure enough 10 mins later, Shaw called and told me they are "managing" all P2P networks since P2P are causing them a lot of "problems"......and they are not targeting anyone or any P2P, they just "manage" and there will be time you could uploads and there would be time where you could not uploads! Well, that' enough for me ....hello Telus ADSL, here I come!

Have a look here: ISP's known to BLOCK or Filter p2p or specifically Limewire There's also possible ways of getting around it without changing isp's.