Is there a way to configure Vim so that it only checks spelling in the text regions of TeX files?
With the vim-latexsuite spell-checking works fine. Since it makes typing latex files a lot easier and faster I can only recommend it to every LaTeX-writing vim user.
Use the project specific dictionary for latex given at http://www.vim.org/scripts/script.php?script_id=499. It will remove all the keywords from being marked by vim's spellchecker.