The main image, title, rating, comments and etc.. are just a node-product-tpl.php that I change to suit my needs. The buy now button which I'm still working on is a view in a custom region that's inside the node template.
The quick tabs themselves are also inserted into a custom region in the node template but then I used two views. one for each tab to grab CCK fields and have the tab/view display them. I've tried to insert the comments onto its own tab but that's a pain as the comments are part of the node body and hard to seperate.
Here's the code in template.php that I use to be able to use custom node regions - normally you can only do custom regions in the page.tpl.php file
function yourtheme_preprocess_node(&$variables, $hook) {
$variables['product_node_price'] = theme('blocks', 'product_node_price');
$variables['product_info_tabs'] = theme('blocks', 'product_info_tabs');
}Then in youtheme.info file you specify the new regions
regions[product_node_price] = Product Node Price
regions[product_info_tabs] = Product Info TabsIn the node template
<?php print $product_info_tabs ?>