Not worth it for me. I checked, and it was substantially more expensive. My closest Costco is only 10-15 minutes away, depending on traffic, and they're building one even closer this year.
I'm waiting for my rebate $ to arrive so that I can buy the 32" LG monitor they have on sale.
Costco PSA: Don't use the actual rebate check to buy the new [insert shiny object here]. The mustachian way is to cash the check, then charge the object of your desire, thus earning future rebates. Costco will happily cash your check. It can typically be cashed out right at the checkstand. When the checks first go out, most warehouses set up a dedicated checkstand just for check cashing, so this is totally legit. Since youre a mustachian, there's zero chance you'll spend the cash on hookers and blow. Don't be tempted by the pizza, either ;-)
And I agree with
@OtherJen. Costco Online is a whole different thing.
One more Costco PSA: If you have a Costco Business Center within striking distance, they carry different merchandise and surprisingly often have lower prices than the regular warehouses. In Salt Lake City, they have a massive combo Warehouse/Business Center, all under the same roof. I didn't notice any particular price differences, but I've only been there once and OMG, was it amazing! We were in an already loaded truck, heading for Colorado, but if we had more space/time, I could have done some real damage.