iStumbler, the free utility for locating AirPort networks, Bluetooth devices and mDNS (Multicast-DNS, or Rendezvous) services, has received an overall face-lift with Release 91, which was scheduled to be issued on Friday. This edition displays icons for various items in the Airport, Bluetooth and mDNS plug-ins, improves the menus and enhances stability, memory and processor usage. Mac OS X v10.3 is required. For US$10, you can receive the next 10 updates to iStumbler a week before they’re posted on the Web. The developer’s Web site had not been updated with the new version as MacCentral posted this article.