Well, probably not. September 11, 2001 was a significant day. September 11, 2010 isn't significant as anything other than an anniversary. And, if we marked all important anniversaries, every day would be special in one way or another. Consider these:
April 29, 1975 - US evacuates it's embassy in Saigon.
May 13, 1897 - Guglielmo Marconi uses radio waves to send a signal over open water. The signal "Are you ready?" crossed the Bristol Channel, a distance of almost 4 miles. Shortly thereafter, Marconi used the same equipment to send a signal a distance of almost 10 miles. From then on, ships at sea could communicate with each other and the mainland even if they couldn't see each other.
May 16, 1960 - Theodore Maiman creates the very first laser beam at Hughes Research Lab in California. And, for a full 40 years, we really had no use for it because it was 40 years ahead of it's time. Now, we couldn't do without them.
Oct. 31/Nov. 1, 1952 - US tests the first hydrogen bomb "Mike" on Eniwetok Atoll in the Marshall Islands. Eniwetok is on the west side of the International Date Line, so it was still October 31 in North America when the bomb exploded on November 1 (local date) on Eniwetok Atoll.
Physicist Herbert York commented on the relatively rapid change from conventional explosives like TNT to atomic bombs to hydrogen bombs as follows:
"the world suddenly shifted from the path it had been on to a more dangerous one. Fission bombs, destructive as they might have been, were thought of [as] being limited in power. Now, it seemed we had learned how to brush even these limits aside and to build bombs whose power was boundless."
November 22, 1963 - Assassination of John Kennedy. Everyone rembers where they were when they heard the news.
December 7, 1941 - Attack on Pearl Harbour by the Japanese Navy.
December 24, 1947 - the day the world's first transistor was successfully tested at Bell Labs.
Just looking at the darn thing, you'd never expect it would ever amount to much. Germanium has since been replaced with the much more abundant silicon, and so that ugly thing in the photo is the great grand daddy of the computer you're sitting in front of and the Blackberry in your shirt pocket.
1978 to 1993 - 24 Global Positioning Satellites are built by Rockwell and launched into orbit 11,000 miles above the Earth. Now, when an airplane goes down or a ship sinks, rescuers can go directly to the site without having to search for it.