So, I decided to put that off for a little while and load of a different map. That was a bad idea since evidentally my heightmap class is broken as well[sad]. I don't know why, but 33, 65, 129 maps load and display perfectly, but my 257x257 map broke it. I'm thinking it has something to do with the fact that I'm using TRIANGLELIST instead of TRIANGLESTRIP, but I'm not sure (yes, I double checked to make sure all of my stuff was being loaded right and that my file was the right size.)
Then, I realized that heightmaps aren't even what I want to use. The only type of map system that seems to fit what I'm looking for is a modelled map. Before I make any more decisions, though, I'm going to write some sort of technical document. I'm not going to be able to switch back and forth between map systems like I can in a 2D game, so I'm going to need to choose one and stick with it.
In good news, I learned all kinds of math and 3D stuff. I know how to calculate a projection matrix, extract the camera's vectors from the view matrix, regenerate axis-aligned unit vectors, etc. Now, remembering it all come tomorrow is a different story. To help myself remember it better and to get some practice I wrote a small software renderer, but I forgot that VS2005 doesn't actually create the solution and such until you tell it to, so I lost it[sad].
Edit: I almost forgot, I also had frame-rate independant movement implemented for the first time ever. Yay!