OK, just in case anyone wanted to know... here is the ratios of all the rares. Or rather, what your chances are of getting the following rares. This data is based on 467 packs:
http://www.pokemonaaah.net/images/20120215.rareratio.png
--- That image shows the percentages of where the ratios converge with more and more packs.
Anyways, this is the final data:
* Nonholo Rare: 49/72 (68.056%, or 1 out of
just under 1.5 packs)
* Holo Rare: 8/36 (22.222%, or 1 out of 4.5 packs)
* Rare (ex): 2/36 (5.555%, or 1 out of 18 packs)
* Ultra Rare (FA-ex): 1/36 packs (2.777%, or 1 in every box)
* Uber Ultra Secret Rares: 1/72 packs (1.389%, or 1 in every 2 boxes)
It took me a while to sort this out, but I figured it had to be some ratio of 18, or some multiple of 18. Anyways, the data support these ratios... so now you know!