Hold on a second -- there's a bit of fine print! If you purchased the second Humble Indie Bundle, you can now also grab the original bundle -- World of Goo, Aquaria, Gish, Lugaru HD, Penumbra Overture, and Samorost 2 -- on your download page. Easy enough.
For new customers, however, there's a little more to it. To "unlock" the first bundle, you'll need to pay over the average contribution price ($7.45 at the time of writing), or increase your payment over this threshold at a later time on the download page. Those sick kids aren't going to know what hit 'em!
More than a reasonable request, if you ask me.