Wow this is quite ironic! I am currently taking a technical writing class in college and today we had to hand in an assignment where we critiqued professional websites.
There are a ton of different things you have to take into consideration like text size and font. Effective use of white space, page alignment, organization of content, design consistency. While i'm not going to critique you on every little thing because i'm kind of exhausted from the paper I just had to write, lol, I'll give a few pointers from what I learned.
To start I would say I like your page it's clear and neat.
Some things to fix may be:
Adding a home hyperlink to the logo, though not a big deal apparently its a convention that many users expect you to have. Even here on Macrumors there's a logo link and a navigation link for the home page.
Your user should not have to use too much scrolling, use the three click rule i.e. no more than three clicks to the end of the page. I would definitely try to condense the footer on the main page there's way too much info down there. You might want to break your main page into a grid or several columns and dedicate one whole column to "Recent Post"
I believe that the "About us" link should be somewhere at the top because that's where most people will look for it. Perhaps put it in the top navigation.
Try to format the "top ten" graphics on the home page so that they are the same size.
I'd like to think the top banner is a work in progress other wise you should probably reduce the dimensions because its not a very effective use of space.
I would consider relocating for facebook and twitter boxes perhaps once again by using dedicated columns like engadget.com which has there facebook and twitter feeds in the right column.
Some text on the front page like an introduction might be nice so that readers understand what they are looking at, something like "Ever wanted to know where the richest countries in the world are or the biggest party songs of the month well look no further we've got you covered!" You don't need to use that exact text but something along those lines.
Aside from that I see you haven't finished but you seem to be on the right track. You're know where near some of these websites
http://www.webpagesthatsuck.com/worst-websites-of-2010.html so your doing good, lol. Good luck
