Yes, but ...
<soapbox>
Two general points regarding content vs. presentation:
(1) The goal is (or should be) not to suppress presentation control, but to
separate presentation control as cleanly as possible from document content.
That is the point of stylesheets --- to provide presentation control, but
to segregate it from semantic markup.
With this in mind, a bit of presentational markup within html may be
tolerable, particularly if it is really purely presentational and does not
get in the way of recognizing semantic/structural markup. A little gif to
make a bulleted list look snazzier, for example, is unlikely to interfere
with recognition of the list structure. But if the list is marked with
alternating gifs of a bold "Q:" and "A:" (indicating that the list is
really made up of question/answer pairs), then the presentation markup has
been used to represent structural information that is lost to any other
kind of processing. Implicit, unrecoverable structure is what should be
avoided.
(2) As I have argued before, it is not possible to *prevent* abuse of
markup. Lacking facilities intended for presentation control, many authors
will bend structural markup to presentation purposes, making it an
unreliable guide to content. Abuse of structural markup for presentation
causes far more trouble than introduction of purely presentational markup.
Providing pure presentation markup --- preferably stylesheets --- is the
best protection for pure content markup.
Ideally, one of the stylesheet proposals would be stabilized and widely
deployed in the very near future, and would be sufficiently rich and
flexible to relieve the pressure for presentation tags in html. I hope it
does happen soon, but I am growing less optimistic. The longer it takes,
the stronger the argument for supporting some presentation markup within
html, to minimize the temptation to abuse structural markup.
</soapbox>
--Michal