If (1) you will be the sole owner of your LLC, and if (2) you do not file Form 8832, then by default your LLC will be treated as a "disregarded entity" for tax purposes. (I emphasized that latter point, because your LLC is indeed a valid entity for all other purposes; this "disregarded entity" thing is merely a fiction designed to make things easier when it's time to prepare the ol' tax return.)
In most one-owner LLC situations, this "disregarded entity" default status is the better choice. It means you don't have to prepare a separate tax return for your entity. You'll report the income and expenses of the business directly on your personal return, as if you were operating the biz as a sole proprietorship. In your personal return you'll include a Schedule C, D, and/or E on which you'll show the numbers for the business (which schedule you use depends, of course, on the nature of the LLC's activities).
Your alternative is to file Form 8832, on which you elect to have your LLC taxed as if it were a corporation. But then you've introduced new (and likely, unnecessary) complexities, such as having to invoke a so-called "S election" in order to enjoy "pass-through" tax benefits, similar to what you'd have by default anyway, if you simply left the LLC as a "disregarded entity".
Two caveats: First remember that this is predicated on the premise that you'll be the sole owner. The previous overview is invalid for a multi-owner company. Also, your question is one for which it's frequently a good idea to buy a little time from a tax professional or accountant. With all the specifics and details of your situation on the desk in front of him / her, you'd get advice that's more customized to your particular scenario.
Best of luck with the new biz!