One thing I noticed in that article is that Sigma didn't list the mounts that they'd be making this lens for or the MSRP.
Now assuming that they do make this one in a Pentax mount, I don't think those of you who are married are going to be able to sneak this one past your wives (the box outside the front door waiting for you will definitely get noticed). If she were to ask you how much it cost, I would find it hard to believe that you could convince her that this lens cost you $100, as opposed to the $10,000 that it may very well cost, even if she doesn't know a thing about camera gear. Even if you were able to convince her that this lens cost a lot more than you told her and she finds out the truth later, that lens may very well be spending it's evenings on her side of the bed.
Even if your wife was OK with you buying this lens, I would speculate that most of you would have to get a second job to finance the purchase of this lens.
Needless to say, I think whoever would get this lens would be a single guy with a lot of money to blow on gear (for obvious reasons).
Needless to say, at least dreaming and drooling are free.
Heather
(whose husband thinks that $200 is expensive for a lens...)