Whats the code to show wordpress categories in php?

I'd like to show my top 10 categories in wordpress, so far here is what i have

<?php wp_list_categories('title_li&show_count=1'); ?>

PHP:

I know that "title_li&" removes the "categories" title and "show_count=1" shows the number of posts within each category.

But id also like to:
~Show only the top 10 categories
~Replace the default bullet list with

»

PHP:

Please post the code if you can help.

Thanks