If you post something to your site should you use a url such as yoursite.com/golf_tips.php or yoursite.com/golf-tips.php? According to this Youtube video by Matt Cutts Google treats hyphens or dashes as separators, but not underscores.
So what does that mean?
If you are trying to make your site as SEO friendly as possible and you post something all about golf tips for example it would be useful if the url or address uses hyphens or dashes.
The particular information you post is all about golf tips. You use a keyworded title and good keyword placement in your post.
Now someone goes to Google to search for golf tips.
Basically what he is saying is you use golf-tips.php you will get better optimization in a search result page. It will be treated as golf tips. However, if you use golf_tips.php you might rank better if someone searched for golftips all one word.
Hyphens and dashes = separators between words. Underscores = no separators between words.
Most of Dolphin 7 pages you post will take the hyphen or dash type of address. There are a few that do not such as about_us.php for example.
If you make custom pages you might consider using hyphens if possible rather than underscores.
If you use Dolphin's Administration to create a page with the builders. It would be wise to create a page that had a format like: Dolphin 7:
Dolphin 7: http://www.yoursite.com/page/golf-tips instead of http://www.yoursite.com/page/golf_tips
Dolphin 6.1x yoursite.com/viewPage.php?ID=golf-tips instead of yoursite.com/viewPage.php?ID=golf_tips
Dolphin 7 does a little bit better job of rewriting pages to be more SEO friendly than Dolphin 6.1x.
It won't help you score or rank #1 in Google without additional SEO optimization and work, but every little bit can help.
Something to keep in mind when building your site and creating new pages.
Underscores are still used. If you look at Boonex.com you will notice most links at Unity use underscores. Things like blog posts, market posts, etc. all tend to use them. Boonex.com might be a little more SEO friendly and optimized if they used hyphens instead. They have been doing it that way for a long time and it works for them though.
The Youtube video was posted on March 06, 2009. Which wasn't too long ago. Most likely this is still the case.
Whether the other search engines use the same concept and idea as Google does is unknown.