It's clean, it's attractive, it's off to a good start ... here's some more feedback:
The flash banner at the top - to me, the motion distracts the eye from the products and "buy" links on the pages . Maybe keep that on the home page only? Peoples' focus will always drift to anything that moves - that's why animated ad banners work (because people get distracted and go off on a tangent). Do you want then looking up there while shopping? Probably not

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On the home page, you have a lot of non-utilized space "above the fold" (namely, the big "Check our Accessories" block. If it were my site I'd prefer to put the most attractive offers up there and maybe put that creative in a sidebar on the right.
I wouldn't put "clear cart" on every page - that option should be available only from the cart viewing page. Why make it easy for them to abandon their carts? Speaking of cart viewing, if the cart could be moved to a small icon along the top it would give more room for product links on the "first read".
I would move the "forum" link below the product pages ... unless you want the forum to be the prime focus of the site?
Technically, you'll probably want to prevent wrapping in the masthead elements - try viewing your page in an 800x600 viewport (altogether possible, on a small laptop running with a minimized browser window) - you get an ugly wrap.
That same minimized browser test will show you how few "calls to action" you have above the fold on the home page - not many!
Also, redirect the "www" to the non-www or vice versa - you already have split page rank

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Hope this helps - good luck!