I am migrating a few WP sites I have to another host. I just backup the sql, backup site and make the changes to the "wp-config.php" file to move over. I was wondering, since I am currently using WP v2.5 on my sites, could I just upload the latest version of WP which is currently 2.7 to the New host, Then just upload my sql, theme and updated versions of all my plug-ins (mods)? Would this work?
Yup. It will work. Just fill up correct WP-config and when you visit your dashboard a message will tell you that your db is outdated and needs to be updated. Go ahead and update and finish. repeat for every blog.
For info a WP plugin for auto upgrade : http://www.zirona.com/software/wordpress-instant-upgrade/ works fine
Yes it's work, also if you want to upgrade your wp ver. why you not install plugins auto upgrade, visit wordpress.org/extend then search auto upgrade, this plugins will help you much with upgrade all of your use plugins automatically...