wilderness - 7:12 pm on Sep 17, 2012 (gmt 0)
Perhaps you could provide the name of the 4th Global-major-SE behind Google, Yahoo and MSN that has appeared since 2003 and without the common knowledge of others?
The "under the theme of potential SE's" has been discussed in this forum many, many times, and before your presence here at Webmaster World.
Prior to 2003 there could have existed other major ranking SE's, however they certainly don't exist today.
Alta Vista was at one time a major bot that has literally disappeared, even though still active.