529 plans...I have one for my DD and I go back and forth about how much to put into it. Here are various considerations:
If you pick the one for your state, I believe most of the time you get to claim your contributions as a deduction on your state income tax return (this may not apply to all states, so check the state you live in). So if your state has a 5% income tax, that's how much of your contribution you can get back on your taxes.
You can participate in any state's 529 plan. Utah's is almost always near the top of the list.
savingforcollege.com is a thorough website and one of the originals about 529 plans and a good way to compare them.
I think for financial aid reasons, a 529 plan is considered a parental asset and therefore only a small portion of it (5.64% max?) is calculated as part of the family contribution. As comparison, 20% of a student's assets are expected to go into the family contribution. So it would behoove you in terms of financial aid to not have much in your child's name.
You as the owner of the account can change the beneficiary. If 1 child doesn't go to college, you can change it to another in the family (you, a niece or nephew, a grandchild). And if there's no one to name as a beneficiary, you can withdraw funds with a 10% penalty in addition to claiming the earnings as income (I think that's all).
If your child gets a scholarship to college, I think that you can take that amount out of the 529 without the above penalty.
For my state's plan, I find changing the allocation of funds restrictive, but at least the expenses are low.
My state's plan is super easy to set up automatic contributions from a checking account (as low as $25 per interval) so it can build without much pain, and you get the benefit of dollar cost averaging.
If you're disciplined enough, sign up on the upromise website and do all online shopping from there, and have your rewards automatically deposited into your 529 account. Free money! But only if you don't carry a balance on your credit cards, otherwise you'll be paying more in credit card interest than any money you'd get in your 529 plan.
Speaking of credit card interest...I personally wouldn't bother with a 529 plan at all until your debt is gone.