The US Mint has published the initial schedule for new products in 2007:

2007 Scheduled Products Listing
The following list displays the United States Mint’s 2007 products and their dates of availability. This list will be updated periodically as dates for products being released later in the year have yet to be set. All dates are subject to change by the United States Mint without prior notice.

Availability Date Product Description
January 10 Jamestown 400th Anniversary Commemorative Coin Program
January/February United States Mint 50 State Quarters Proof Set™
January/February United States Mint 50 State Quarters Silver Proof Set™
January 29 Montana Quarter Bags and Two-Roll Sets
February 5 American Eagle Gold Proof Coins
February 5 American Buffalo Gold Proof One Ounce Coin
February 15 United States Mint Presidential $1 Coin Proof Set
February 15 George Washington $1 Coin Bags and Rolls
February 20 Golden Dollar Bags and Rolls
February 20 Kennedy Half-Dollar Bag and Two-Roll Set
March American Eagle Silver Proof Coin
March/April American Eagle Uncirculated Coins
April Washington Quarter Bags and Two-Roll Sets
April United States Mint Proof Set(R)
May Presidential Spouse Gold Proof Coin
May Presidential Spouse Bronze Medal 1 5/16″
May John Adams $1 Coin Bags and Rolls
May Little Rock Central High School Desegregation Silver Dollar

I’ve highlighted the products related to the new Presidential $1 Dollar Coin Program. Note that there is a proof set for the Presidential Dollar coins, but not a silver proof set, at least, not as of May 2007.