There are two issues here; the bandwidth your ISP provides on the upload side, and the bandwidth the remote website provides between you and its server(s).
As far as the ISP, your typical consumer-grade plan is not intended to support uploading in any great capacity. In fact, the ISP wants to discourage it since it suggests you're providing services to others on your local network. In that case, he wants you to upgrade to a business-grade plan to increase your speeds and throughput. But for the rest of us nobodies, the ISP’s mindset is to provide just enough upload bandwidth to support the download side of the connection (primarily, response messages).
That’s a long way of saying, if you want more bandwidth, you need to pay for it!
As far as YouTube, any website is likewise limited in its capacity to accept uploads (either w/ its own ISP and/or servers), and is always going to show deference to its paying customers (“partners”). So even if you increased your upload bandwidth w/ the ISP, it doesn’t mean you’ll necessarily be satisfied w/ the bandwidth available between you and YouTube (or any other similar website), not unless you too become a “partner”.
Well I actually do know, that because we had so much trouble and complained to our Network Company twice a week, we got upgraded a lot, but still pays the same.
I don't know if we got upgraded to business-grade though.
And yeah about the youtube partnership, my problem is that Youtube wont let me become a partner because of the country I live in.
But I can always become a partner with others ( like Machinima,TGB and others) though.