Is the card valid immediately? What are the main restrictions, if any?
Yes, valid as soon as you get the email link which is just a few hours. Read the details for the restrictions. Mainly you can only use this for eBay items which is not really much of a restriction because that covers a lot of territory. I plan to use it for purchasing more coupons.
I almost forgot. Only ONE eBay gift card sold via this deal per person. My first thought was to buy 10 of these gift cards so like getting $150 for $70 but they restrict you to only buying one.