Today is Tax Day in the United States, even though it is April 18th. The date is postponed from April 15th to the 18th because of it falling out on a holiday and then being pushed off until the next business day.
None of the search engines have special logos. Google, Yahoo, Bing, Ask.com and so on all are going standard today. Not that one would expect a fun, lighthearted logo on a day where you potentially can shell out a lot of money.
That being said, we have a theme and I wanted to make sure most of you saw it.
Happy Tax Day for those getting refunds, the rest, I am sorry to rub it in.
Forum discussion at Search Engine Roundtable Forums.