8 days. Oct. 17th, Wednesday (next Wednesday), is when time runs out and Jackson would officially become the Rockets.
The first day was October 1, that is when the Warriors officially received the offer sheet, hence the first day. So on the 16th the Rockets will find out if they get Jackson. But will probably hear from GS before then.
An article dated Oct. 3rd said that they had received the sheet the day before and had 14 days from the current date (the 3rd) to match and offer. http://www.sfgate.com/cgi-bin/article.cgi?f=/chronicle/archive/2001/10/03/SP166342.DTL
I wouldn't pay as close attention to the date as I would to the GSW boxscore to make sure none of their big men get hurt