The version of tufte-latex on CTAN is v3.5.0
\ProvidesClass{tufte-book}[2009/12/11 v3.5.0 Tufte-book class]
while the latest version here is v3.5.1
\ProvidesClass{tufte-book}[2010/03/28 v3.5.1 Tufte-book class]
Can one of the maintainers of Tufte LaTeX submit the updated
version to CTAN? The upload instructions are here
This would be an enormous help as one of the version differences
is the nobib option, thus allowing people to use the tufte-* classes
with biblatex and biber.
Cheers,
-j