I hope they release it in Pentax mount, but may I ask you why you are interested in this lens?
If it the macro ability, then there is the Pentax/Sigma 50/2.8, sigma 70/2.8. If it the spped then we have 50/1.4, 55/1.4, 77/1.8.
Do you think there is use for both macro and f2 (such narrow dof ?), or is it the price.
I am not questioning your decision at all, but rather curious to learn why? Just a year ago, I posted a thread asking what is the use of a 135mm lens in APS-C, and now my F135 is my third favorite lens, only behind my two FA limteds. Also, a few months ago, I thought I will never get the 24/2 as I didn't find a use for it, now it is my favorite walk-around lens. So, It is a genuine query to understnad better......
Thanks!
--
http://www.pentaxphotogallery.com/home#section=ARTIST&subSection=2323984&subSubSection=0&language=EN
K10D, K-7
Pentax Primes: DA21/3.2, FA*24/2, F28/2.8, FA35/2, FA43/1.9, FA77/1.8, F135/2.8
Sigma Zooms: Sigma 10-20, Sigma 100-300 F4
'Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming... 'Wow! What a ride!'