Hillary seems to be moving closer to a run:

According to participants, it is clear that Mrs. Clinton is far along in plotting a campaign, and she is honing strategy at the same time that she is making overtures to people in states that heavily influence the presidential nominating process. New Hampshire is expected to hold the first primary in January 2008, after caucuses in Iowa and Nevada.

Mrs. Clinton has gone to great lengths to try to keep these meetings private. She and her aides have strongly asked Democrats not to report what has taken place there, from what she says to what she eats and where (she had the lamb at Ruth’s Chris, the Dover sole at the Four Seasons).

It sounds from the article like the current strategy is for Hillary to announce she is forming an exploratory committee in January, but hold off for a period before formally entering the race, so she can get some accomplishments under her belt in the new Democratic Congress.

I think that's a good strategy. When you have a profile that high you don't need to increase your name recognition. It's better to build slow and steady. It's not like we all don't know she's running.