I am amazed at how mushy my brain is getting. I seem to have completely lost the concept of basic math, I am relying on my GPS more than ever before, and it feels like it takes me longer to grasp some concepts. Please tell me this gets better at some point (even if it's way in the future, it will give me something to hold on to).
Re: does the pregnancy brain-mush get better?
Ditto this exactly! If I do end up remembering the word I want, it definitely takes longer - I'm just not as quick anymore.
TTC #2: BFP 12/17/11, m/c 1/7/12 and D&C 1/12/12
baby blog/cooking blog

In my experience, I don't think it has gotten better. I've just gotten better at coping with it.
(my downfall was forgetting stuff. Forgetting why I entered a room, forgetting something at the grocery store, forgetting to respond to an email, etc. So now I am Queen of Lists...waaaaayyy more than before...and when I'm going upstairs I focus on *why* I'm going & don't leave until I look around & make sure I have everything I need)
For me, it did get better post-pregnancy. It was bad with DD and even worse with DS. I was repeatedly shocked at how true "pregnancy brain" was. A sampling: I completely forgot a dentist appointment, paid the mortgage twice in one month, would get lost on semi-familiar driving routes, and would ALWAYS lose my train of thought mid-sentence. To the point where DH would see a familiar look on my face and be like, "It happened again??" And along with Artslvr, I was SO clumsy - even before third-trimester awkwardness set in. I dropped things constantly...always fun in the grocery store when you have to request a "clean up in aisle four."
But I operated better on sleep-deprived brain than I did with pregnancy brain. And now, almost a year out from pregnancy, I think my mind is sharper in some ways. I always have a hundred things running through it, so I'm forced to compartmentalize, prioritize, and multi-task (at least in my head), often at a quick pace. I just don't have time to dwell on the unimportant stuff, be indecisive, etc. So hopefully it'll be the same for you!