Widgetizing theme, and creating custom widget plugin

I have a few books I’ve been following on this. I made my own custom WP theme, which works fine, however I decided I wanted to make the right sidebar a widget area, and turn my twitter feed into a widget instead of hardcoding it into the template. I understand there are tons of twitter feed plugins out there, however I am doing this for the experience.

Plugin file:


class sp_twitterWidget extends WP_Widget 
{
    function sp_twitterWidget()
    {
        parent::WP_Widget(false, $name = 'Custom Twitter Feed');
        return;
    }
    
    function widget($args, $instance)
    {
        extract($args);
        
        echo $before_widget;
            echo $before_title;
                echo $instance['title'];
            echo $after_title;
            
                $api_url = 'http://api.twitter.com/1/statuses/user_timeline.json?screen_name=';
                $twitter_data = file_get_contents($api_url);
                $twitter_data = json_decode($twitter_data);

                for ($i=1;$i<=3;$i++):
                    echo '<p class="tweet">';
                    echo $twitter_data[$i]->text;
                    echo '<br /><span>';
                    echo date("F j", strtotime($twitter_data[$i]->created_at));
                    echo '</span></p>';
                endfor;
            
        echo $after_widget;
        
    }
    
    function update($new_instance, $old_instance)
    {
        return $new_instance;
    }
    
    function form($instance)
    {
        $theTitle = esc_attr($instance['title']);
        
        echo '<p>';
            echo '<label for="'.$this->get_field_id('title').'">
                  Title: <input class="widefat" id="'.$this->get_field_id('title').'" name="'.$this->get_field_name('title').'" type="text" value="'.$theTitle.'" />
                  </label>';
        echo '</p>';
    }    
}

add_action('widgets_init', create_function('', 'return register_widget("sp_twitterWidget");'));

Registering sidebar as a widget-area:


if (!function_exists('register_sidebar')) { register_sidebar(); }

function sp_rightSidebar()
{
    register_sidebar(array(
        'name'          => 'Right Sidebar',
        'id'            => 'rightColumn',
        'description'   => __('The widget area for the right sidebar', 'simplePortfolio'),
        'before_widget' => '<div id="%1$s" class="widget %2$s">',
        'after_widget'  => '</div>',
        'before_title'  => '<div class="rightHeading">',
        'after_title'   => '</div>'));    
}

add_action('init', 'sp_rightSidebar');

Sidebar theme file:


<div id="rightColumn"> 
        <?php if (!function_exists('sp_rightSidebar') || !sp_rightSidebar()): ?>
        sp_rightSidebar is waiting.
        <?php else: ?>
        <?php dynamic_sidebar('sp_rightSidebar'); ?>
        <?php endif; ?>    
</div>  

No matter what I do, it always displays “sp_rightSidebar is waiting on the sidebar”, I have tested my widget plugin with other themes and it works fine, so it has to be something about my sidebar theme file/not registering the sidebar correctly I’m assuming. The “Right Sidebar” widget area does display in the widgets area in the admin panel, however anything added does not stay there.

I hate to be the guy who dumps his code asking for people to take a look, but if you see anything that could be wrong, I’d appreciate your input.

Thanks!