Vertical search company Oodle launched in late March, and that raises the perhaps not-so-obvious question: How many other Internet search-related companies are playing off positive associations of the Google name by also including the "oo" sound in their names?

There's Oodle, of course. And Kanoodle. And Accoona, which launched to great fanfare a few months ago. And ooBdoo, which re-launched on April 6 to include new MP3 and image search functionality. Searchblog lists a handful of other search companies with the "oo" -- Mooter, Sootle, Soople and (if you stretch things) LookSmart. The original, of course, was Yahoo.

What is this "oo" sound called? Doing a quick search on Google turned up a few possibilities -- the "variant vowel oo" and the "digraph oo." Any phonetics or linguistics experts out there who can help?

It reminded me of the Wikipedia entry for the heavy metal umlaut, in which one single sound carried a number of connotations and implied meanings: "A heavy metal umlaut is an umlaut over a letter in the name of a heavy metal band. Umlauts and other diacritics with a blackletter style typeface are a form of foreign branding intended to give a band's logo a Germanic or Nordic "toughness". It is a form of marketing that invokes stereotypes of boldness and strength commonly attributed to peoples such as the Vikings."

With that in mind, what does the "Internet oo" connote?