Add a backgropund to the News section and the We Provide section to make them more distinguishable from the middle text. Also, add a little more spacing between the left column and the middle column. Also, the Mail Priority list is not alligned in Netscape
I think that the colors used in the webdesign are too much contrasted, try to use colors with more value (more white in the color that black) and use choose carefully the font colors. That will make it, keep goin'!
I think you have too many different font sizes happening in your site. Some of your main area text are bearly readable and being grey does not help. (By the way, I'm using IE6 with font display size set to "smaller".)
In your interior pages, the header ia not as tall. I understand that is because they do not have the Account Login box and I see that you've made a smaller logo to use. However, whatever that equipment unit thing is looks decapitated.
Back to your main page. In the center, underneath your 4 plans boxes, you have the text links to "Terms of Service ... Want to be a Reseller? ... More Plans". You can do this better. They are lost amongst that jumble of logos.
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