Definitely to reiterate Dana, need more info about the specifics because yes there could be disastrous effects if not done properly.
Besides meta refresh, there are other things to consider. Probably most importantly is the positioning of the home page in search results for the 'product'. If you are ranking top 5 for your product keywords, and the ranking page is your home page, you may find that when you rework your home page to reflect your brand, you lose that positioning.
If you were moving from one landing page to another (i.e. /products to say /products/buy, it would be a bit different because you could 301 the /products page and officially tell Google and other SEs that you are simply moving the page. You cannot, obviously, do this with the root domain (301) or that would defeat the branding purpose.
I would definitely check positioning and revenue for your money keywords first. Also, once you move the product, i would at the very least have a link in the main navigation of the home page that links directly to the product with the appropriate anchor. If you only have one product, or one product set, i would also encourage you to optimized the URL (i.e. instead of /product it could be /
Still need more info to make solid recommendations.