Originally Posted by SimonSays

One thing that should be tested along with the call-to-action phrases is the action taken when the potential customer hits that join page to which the phrase is linked. While it's certainly important to get more customers to your join page, it's not so good if the action that they're taking is to back up to the previous page on the tour or close the window.

Some sponsors use "Next Page..." or "See More..." as links to their join pages on their tour, and this historically means a lot of hits to the join page but low signup ratios. On the other hand, replacing the "Next Page" link with "Join Now" or a similar clear statement will get fewer clicks to the join page but a better ratio of actual signups from those who click that link.

The real key, as mentioned by others, is matching the call-to-action to the look/feel of the tour, the specific product, the content and context of the tour, the offer, the copy platform and the traffic sources.

On pages like galleries, free sites, blog posts, and other pages designed to get people to the first tour page, then offering them "more" of what they're seeing is a good way to move them to the tour. Not saying just use the word "more" as the link, but that telling someone that clicking a link will give them access to more of what they like is good on those kinds of pages.