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<p>This plugin stops access to your signup page, except where the visitor has been invited and clicked the link in their invitation email. Your users invite people, and you can see who has sent the most invitations, and how many resulting signups have occurred. Other features:</p>
<ul>
<li>Restrict the ability to invite people to users who have been registered only for a certain number of days or more</li>
<li>View the number of invites sent and resulting signups per month</li>
<li>View the users who have sent the most invites, and the number of resulting signups</li>
<li>Browse all invitations sent (auto paginated)</li>
<li>Change the default email text</li>
<li>Set after how many days an invitation will expire</li>
<li>Works with different locations of signup page (default: /wp-signup.php)</li>
<li>Set the message to show if someone tries to sign up with no valid invitation</li>
<li>Turn off security on signup form, allowing anyone to sign up (this does not affect the ability to invite people)</li>
<li>Show an invitation form on the dashboard</li>
<li>Show best inviters on your site with a shortcode</li>
<li>Set any number of special codes with which people can sign up without being invited</li>
<li>View reports on the number of people who have signed up with each code</li>
</ul>
<p>This plugin is based on the invitation plugin by kt (Gord) from http://www.ikazoku.com.</p>
<p>There are a few extra features introduced in version 0.9:</p>
<h4>Introducer points system</h4>
<p>Each time somebody (Person A) invites a friend (Person B), and Person B signs up, Person A is awarded 5 points. If Person B invites someone (Person C) and they sign up, Person A is awarded 2 points. And if Person C invites someone (Person D) and they sign up, Person A is awarded 1 point (and, of course, Person B is awarded 2 points). Using this pyramid-like system you can see who is inviting not just the most people, but the best kind of people.</p>
<p>The introducer points are stored in the users meta table with the key <code>secure_invite_points</code>. You can retrieve a persons points using this function: <code>get_usermeta( [user ID], "secure_invite_points" )</code> substituting [user ID] for their actual user ID.</p>
<h4>Bulk deletion of invites</h4>
<p>As an administrator you can now select multiple invitations and delete them. This is much better than the one-at-a-time deletion method in previous versions.</p>
<h4>Shortcodes</h4>
<p>There are three shortcodes available:</p>
<p>1) By using the [inviteform] shortcode you can place an invitation form on any post or page.</p>
<p>2) Using [bestinviters] will show a list of the top 6 inviters by points, with the points they have currently got.</p>
<p>3) Using [myinviter] will show the diplay name for the person who invited the current user. Using [myinviter id=”123″] will show the display name for the person who invited the user with ID 123.</p>
<h4>Automatic BuddyPress theme integration</h4>
<p>If your BuddyPress theme is the default theme (for BuddyPress version 1.2 or above), or a child of the default theme, or uses the same template hooks as the default theme, you can put the invitation form in the following places by just ticking the right box in your settings screen:</p>
<ul>
<li>Before any list of members</li>
<li>After any list of members</li>
<li>At the top of every page</li>
<li>Before your site homepage</li>
<li>After your site homepage</li>
<li>At the top of the default sidebar</li>
<li>At the bottom of the default sidebar</li>
</ul>
<p>The invitation form is hidden by default, and is shown by clicking an “Invite a friend” button which makes the form slide into view.</p>
<h4>Preset settings</h4>
<p>If you want to quickly set up invitations without messing with lots of settings, there are now four presets you can use:</p>
<ul>
<li>Anyone can join with or without an invitation, and all users can invite as many people as they like</li>
<li>Signup is just for invited people, and all users can invite as many people as they like</li>
<li>Signup is just for invited people, and all users who have been registered for 30 days or more can invite as many people as they like</li>
<li>Signup is just for invited people, and all users who have been registered for 30 days or more can invite up to 10 people</li>
</ul>
<p>Or you can use your own custom settings just as before.</p>
<h4>Overriding of special users</h4>
<p>Sometimes you want particular users to be able to invite more friends than the default, or perhaps you want to stop a particular user from inviting anybody at all. Now you can, by searching for the user and changing their own individual settings. You san set whether they are allowed to send invitations at all, and of so how many (either a limited number or unlimited).</p>
<h3>To-do</h3>
<p>Next on the list for this plugin is the ability to invite multiple people at the same time (with the same message).</p>
<p>Then, adding the ability for site admins to only allow hand-picked users to send invitations (thanks to Tuomas for that suggestion here: http://www.stillbreathing.co.uk/blog/2009/01/14/wordpress-mu-plugin-secure-invites/#comment-24240).</p>


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