Full Day Kindergarten

What are your thoughts on full day kindergarten? Our school district is offering it for the first time next year and my 4-year-old will be in the class.
Advantages:
More education, better for working families
Disadvantages:
Long days for little kids, less time with mom
I need help adding to the advantages/disadvantages. Do you have any suggestions?
Here's an article from the Clearing House on Early Education and Parenting looking at the switch to full day kindergarten.
There has been a trend away from half-day or alternate-day kindergarten schedules and toward full-day kindergarten in many school districts. "In the fall of 1998, about 4 million children were attending kindergarten," says a National Center for Educational Statistics study. "[Fifty-five] percent [of kindergartners] were in full-day programs and 45 percent were in part-day programs" (West et al., 2000). Changes in American society and education over the last 20 years—such as the increase in single-parent and dual-employment households and the fact that most children now spend a significant part of the day away from home—have contributed to the popularity of all-day (every day) kindergarten programs in many communities (Gullo, 1990). Studies show that parents favor a full-day program that reduces the number of transitions kindergartners experience in a typical day (Housden & Kam, 1992; Johnson, 1993). Research also suggests that many children benefit more, academically and socially, during the primary years from participation in full-day programs than from participation in half-day kindergarten programs (Cryan et al., 1992; Karweit, 1992; Gullo, 2000; Rothenberg, 1995).
-NewsAnchorMom Jen