Giga,

I think your homepage should be the JUST of your whole site idea. Meaning, write a brief summary or article about what your entire site is about, what people can do from your site. Then just below that, you can do a weekly blog or update informing your visitors about new features, new pages, etc.

I guess the idea is to keep your visitors intrigued with information on your homepage each week. It doesn't have to be formal or anything, just tell the truth and be yourself.

The best way to do all the above is to see yourself as one of your visitors and think about what you would expect to see on your site.

Hope this helps

KevinCamon