with date/times like you have, there are fractions of a second too, in your query you use 'Aug 19 2009 4:29:03:000PM', the screen capture only shows seconds. if you want an exact match like you are doing you need to know the entire time:
select convert(char(23),YourDate,121) FROM YourTable
try "flooring" your date: http://stackoverflow.com/questions/85373/floor-a-date-in-sql-server
KM
2009-08-19 21:30:35