If you can wait just a couple of weeks Slack-10.2 will be out. If you want to upgrade Slackware, you should read Pat's
UPGRADE.TXT file and follow his instructions.
Also note that Gnome is not in Slackware -current, and will not be included in new releases of Slackware. Pat recommends some third-party places to get Gnome if you choose that DE in the -current
ChangeLog.txt