The pdfsync commands rely on the applescript capability of the viewers like Skim. I don't think that is going to be possible with xdvi.
That, and the inclusion of the package pdfsync, so that the pdf contains pointers to the original lines. So I don't think you'll have much luck trying to get something like that to work with xdvi.
No - two-way syncing does work properly with xdvi, and in fact did so for a long time before pdfsync. The required information is embedded in the dvi file, and, for example, both BBEdit and emacs are able to easily synchronize both ways with xdvi. You just need to call xdvi with the line number and file names as arguments (i.e., xdvi - sourceposition lineno$texfile $dvifile), and xdvi goes to the right page with a marker at the appropriate location. And if you set the 'XEDITOR' environment to 'mate -line %l %f' then clicking on xdvi takes you to the right line in TextMate.
If the processing time of pdflatex is the issue for you, then I'd suggest you cut up your source file into pieces, and run it on the pieces.
Thats a fair enough point. It is just that recently I've been working on a very long document that doesn't split conveniently into chunks less than 50 pages, more in places, and it needs to be repeatedly typeset because I make lots of errors when typing math equations (duh).
But perhaps more than that, it does seem that one _should_ be able to make syncing work between TextMate and xdvi, given TextMate's vaunted flexibility and power.... Perhaps someone can point me to the code that enables syncing from TextMate to Skim, and tell me what it means, and I can try to hack it to work with xdvi?
Geoff