Do you validate your HTML code

HI,
Few weeks back I found a post on top25web SEO forum about search engines and valid HTML code. Querry was to find out wheather search engines give more priority to site having valid HTML code i.e. 100% error free. well as inour SEO community all don't have same belief some say its important to have valid HTML code other just said it doesn't matter.

I generally validate my sites (projects)at the start and after that doesn't bother for validating. Generally use W3C HTML validator for that.

So to find out answer to the querry I juss searched three search engine for Search Engine Optimisation keyword and found around 75% results contain HTML errors.
TO my utter surprise search engine themselve containg errors...Only exception was MSN

Below are the stats:

1. 1st place - MSN - Passed!
2. 2nd place - Altavista - Failed, 38 errors
3. 3rd place - Yahoo - Failed, 41 errors
4. 4th place - Google - Failed, 61 errors
5. 5th place - Ask.com - Failed, 64 errors
6. Runner-up - Dogpile - Failed, 70 errors

What do you people say now!!!!!!!!!!!