According to Treasure Capsule Online Shop, a new TV anime series of "Pretty Cure" following "Yes! Precure 5 GoGo!" will start on February 1st 2009. The information indicates that there are three main characters. The title of the new series has not been given yet.

Source: Treasure Capsule Online Page 1
Source: Treasure Capsule Online Page 2

Edited on Nov 14th==============
According to Japanese Patent Office Trademark database, the title of the new Pretty Cure series was revealed to be "Fresh PreCure!".

Source: Patent Office Search Engine (Category: 4, ID:2008-083652)
Source: the title logo of Fresh PreCure

Edited on Nov 15th=================
According to the official website, the 5th movie "PreCure All Stars" will be shown in the spring 2009. It's a special movie cerebrating the 5th anniversary of the start of Pretty Cure series.

Source: Official website

Edited on Nov 27th=================
The official website was opened.

Fresh Precure! Official Website

Edited on Dec 9th=============
An image of the three main characters leaked.