The "support twitter updates" looks like a tagline and the categories are confusing. A standard menu would be at the top right of the page with Updates/About/Contact/Support as options.
The "screenshot" of the product on the top right is confusing.. it looks like clickable UI elements at first.
The buy button does not have enough contrast and the desired action is not clear enough. Plus why is the sale price on the button? Was that tested?
The fact that this is on sale is not immediately obvious.
The screenshot of the product's menu should be next to the mouse, perhaps overlapping.
The manual portion is superfluous and should be on the support page or on a separate "How it works" link.
The background is nice but really distracting.
Finally the phalanx of share buttons at the top is highly distracting and might be better placed somewhere else. I would probably put a grey band at the top with the share links on the left and the support/about menu items on the top right.
I would also move the screenshot next to the mouse, put the sale price info above the buy button and move the buy button down onto the grey section to provide more contrast (plus I'd try the button in the orange/yellow). The text between sale price and the app store logo should go below the buy button to the right of the other grey text.
The copy could also be tightened up.. for example "Instantly achieve unrivaled precision with any mouse." is a much tigther value proposition.
The grey bullet points should be shortened and more clearly delineated.
Finally the FinalTouch logo has too much glow and makes my eyes bug out.
Note: I'm not trying to denigrate the owner's website. This is an unsolicited random opinion.