IMO, anyone who has used the DA 35ltd extensively would reconsider a FF-only self-imposed restriction
And Nikon has just released a DX (1.5 crop) HSM digital-only 35mm f/1.8 lens with reportedly better optics than their FF 35 f/2 -
for $199 MSRP.
The DA/DX lenses give you some advantages over FF lenses - one of which is a lower price because less glass is needed.
And, sadly, I think the likelihood of Pentax going FF is shrinking monthly. We'll not see it in 2009 or 2010, and I personally don't think we'll see it.... ever. The market will have to be changed by a manufacturing process that makes the sensors cheaper - either economy of scale (not likely,) or some real breakthroughs in the technology.
Pentax needs to make up too much brand-loyalty ground to catch up to Nikon/Canon, and Sony's camera division is just like a hobby to that huge company - they can do whatever they want, fail, and it almost doesn't matter.
I'd like to be wrong.
However, you can still take advantage of FF lenses on film, so it's not a wash.
.