Bigger text
In comparison to older-style websites, many "2.0" sites have large text.
You will get more room when you fill less stuff on the same amount of space.
When you've made more room, you can choose to make more important elements bigger than less important elements (if they're still there).
Making things bigger makes them more noticeable than less important elements. All through the history of on headings, print design, headlines and title pages; such an effect has been used.
Not only does big text stand out, but it's also more accessible to more people. That's not just people with visual impairments, but also people looking on LCD screens in sunlight, people sitting a little further from the screen, and people just skimming the page. If you think about it, that could be quite a lot of people!
When & how to use big text
Big text makes most pages more usable for more people, so it's a good thing.
Needless to say, size is relative. You can't take a normal, busy site, make ALL the text bigger, and make it more usable. This may not work. It may turn out to be worse.
In order to use big text, you have to make room by simplifying, removing unnecessary elements.
It is also necessary for you to have a reason in order to make certain text bigger than the rest. Moreover, it is important that the text should be helpful and having an important effect. It would be foolish to add big text simply because it is oh-so 2.0!
If you need to have a lot of information on a page, and it's all relatively equal in importance, then maybe you should keep it all small.
