Netflix HD uses about 4-6 Mbps.. you should be fine.
Even though Earthlink says 7mbps, you'll probably get 10mbps. It's still TWC, you'll still get billed by TWC... though you get support through Earthlink, email goes through Earthlink if you use the ISP's email, etc. That's how it was when I had Earthlink around 5-6 years ago. They might use a little different routing than TWC, though I can't remember.
Even though Earthlink says 7mbps, you'll probably get 10mbps. It's still TWC, you'll still get billed by TWC... though you get support through Earthlink, email goes through Earthlink if you use the ISP's email, etc. That's how it was when I had Earthlink around 5-6 years ago. They might use a little different routing than TWC, though I can't remember.