I think that we can come to the conclusion that those images are not enough evidence for Pentax future lens plans. Pentax is a tight lipped company now, almost leak proof (they leak when set under considerable pressure, like the week before the K-7 announcement...). I have heard nothing about new D FA Star lenses, but yes Pentax may well be considering them for an eventual future 24x36 in 5 years or whatever - but 50 f/1.0 is hard to believe. Pentax made a 50 f/1.2. A 50 f/1.0, hard to believe as a new standard lens for a 24x36 system. Would be more logical with an update of the 50 f/1.4 design. As for 20 f/2.8, well they have the design already - with some minor tweaks, why not? But wouldn't it be more logical to have sort of standard zoom and telezoom as first lenses for a new camera system instead of going for rather extreme primes... Neither the 20 f/2.8 or 50 f/1.0 can be considered as being standard choices for the everyday 24x36 shooter.
DA Star 400 - yes, Pentax has been working on one and it is a logical follow up to the 300. But it is "written in the stas" if it actually will be released. If the K-7 becomes the success we all hope for, so yes. I do believe in a 400 for the APS-C.
DA 135 Limited... well, I would want one. Really I would. I love 135. I have the FA 135 f/2.8 and loves it, one of my most used lenses. But 135 f/3.5 or f/3.2 sounds logical for a Limited. Or a 125 f/2.8. You now, Limietds are also about odd focal lengths. 135 is too normal.
But then, 35 and 70 are quite normal lengths on APS-C so 135 is perhaps not odd for a Limited. Anyway, there has been talks for a long time about a more tele version of a Limited. Let's see what happens.
I do believe the Limited zoom was canceled many years ago, Limiteds are all about primes now. (Pentax did thought about a zoom in the late 90's, but it never surfaced. One idea was to have a 3 focals in one lens, so not really a zoom the classic way. I believe there used to be a Leica with this idea some years back...).