The results here are all so erratic. I just re-tested with my 18-135 and found that the lens name is now shown in RAW and JPEG images, whereas K-Three shows that it does for his JPEGs. The fact that it works now for me may have to do with the recent OS X updates which I've all installed. But why doesn't it work for K-Three then?
(This reminds me of an obscure issue I found out a few months ago where I pointed out that certain flash operations did not work correctly with the K-3:
https://www.pentaxforums.com/forums/172-pentax-k-3/254837-hss-sometimes-not-w...confirmed.html)
Then, today, I noticed yet another irregularity: My SMC 50mm/1.7 does show up in some pictures correctly as "A Series Lens", while it's blank in others. Between those shots I had different lenses on the K-3, and after re-attaching the 50mm all the images in row were having the problem, while all others before were good. So, this suggests that the lens ID was not properly registered by the camera when re-attaching the lens. Oddly, though, all other parameters were properly identified, such as the aperture (which was most times at f/1.7, and I had no other lens used with that wide aperture). I then checked the EXIF data with exiftool and found that the correctly identified lens has the numeric values "2 0", whereas the images with the blank lens had "2 215". This is most surprising because whereas 0 indicates a "don't know" value, 215 is rather specific and should be identifying the precise lens. This is all so weird. However, this effect with my 50mm lens is different from this thread's main topic because the main topic's issue does not have this variable Lens ID issue. It's just irritating me how this is all coming up now, one small problem after another, all with my new K-3.
Now, back to the original issue. Below are two screenshots from my current. As you can see, both RAW and JPEG show the Lens name correctly. So, for me, the issue of this topic appears to be fixed. Remains to be seen why K-Three still has trouble (but with JPEGs only, while my original issue was with RAWs but _not_ with JPEGs). Same with NZ_Ross.
@NZ_Ross - have you updated all your Mac software in the past days, including OS X 10.9.3?