This probably goes more towards having visitors visit your site numerous times rather than just once, but I suppose it could apply to registering as well. Firstly, you want to make your website eye-catching. It has to look like a friendly atmosphere for visitors to become a part of. This can be done by creating your own graphics that are integrated into the site design. For a site design, you want to use bright, vibrant colors (sometimes contrasting ones to make them stand out more). Propaganda works well, too. It might be a good idea to advertise your website in your signature on forums relating to the same subject matter of your website and asking other websites with the same subject matter to link to you. In your site description, try to make visiting your website sound like a one-of-a-kind experience. Use descriptions like "best", "number one", "critically acclaimed", etc. These are great ways to start and can easily be expanded upon!

The key to to have everything that is needed in one spot, like a nice title in the left hand corner and a navigation bar under or above it. Also a good way is to get your important links like login, register, copyrights, or your private policy in one spot. A good example is www.playlist.com

Honestly, the easiest way to get people to register on your site is to have something they want, be it info, a service, or a product.

All the tips you gave were good to but it ultimately comes down to wither or not they want the stuff your website has to offer.

Also one other thing, DON'T OVER LOAD THEM. If you have 500 different things on your site it is hard for peopel to find what they want. Sure little cool things liek shout boxes or forums or that really awesome video you saw are nice to have and share but direct your visitors to what they are there for. In short keep the site about what the site is about.

I see a lot of sites that have loads of different things on their main page and it almost looks like they are trying to create a new social networking site all in one page.

Also keep the graphics to an ok amount. If your site takes an hour to download then people won't care what you have.

Also make sure your site is coded correctally, verify it with WC3 to make sure it can be viewed on all browsers (this is especially important with the rise of cell phone internet)

IF you have an online product and the ability, one of the BEST THINGS EVER is live support via chat. When I go looking for a product on the net (Especially if i am unfamiliar with said product) I LOVE to see that little "live online help" sign. Even if I never use it it makes me feel good to know that if i need help there is someone who i can contact.

These are just a few things to help. There are LOADS more but if you really need ot know what is up go googling it, remember the best ideas (and most profitable) are researched A LOT even before you get your site.