[wp-testers] Thumbnail Question

[lucaskeiser at keisermedia.com]

I added a featured image (150x150) while the twentyten theme was active. Later I changed themes and the featured image setup is supposed to be 616x149 yet the display is still 150x150. Is there something I am doing wrong or is this a bug?

<?php if( has_post_thumbnail() ) : ?><a href="<?php the_permalink(); ?>"><?php the_post_thumbnail(array(616, 149), array('class' => 'imgcenter-border')); ?></a><?php endif; ?>