The Back_Migrate module has a setting for which tables to include only the structure. I would do that for all cache tables, sessions, and watchdog. Depending on what you use accesslog for, that one maybe. (Actually, I try to discourage accesslog use entirely.)
Nancy Injustice anywhere is a threat to justice everywhere. -- Dr. Martin L. King, Jr.
From: Ursula Pieper
Additionally to all great advice above, I would empty the cache just before dumping the database.
When setting up a new mysql installation, it is useful in the long run to make sure that the default character setting is uft-8. I wrote a tutorial about that a while ago, because I ran into issues with the feed aggregator: http://upsitesweb.com/blog/2011/08/drupal-7-feed-aggregator-issue-mysql-char...