6-17-11 Update: The southbound lane of River Road is now using the middle lane. The northbound lane is using only one lane in areas. Both lanes are experiencing some slow-down.
Turning off from River Road onto a side street can be difficult, and http://www.keepusmoving.info/proj_riverroad11.html states that "drivers may experience 10-15 minute delays when entering or leaving side streets and driveway". There are many high "curbs" to navigate, and the roads are less then ideal.
I still advise people to avoid the area when they can. People can use take the Northwest Expressway and use Maxwell Road, Beltline, or Irving Road (among others) to avoid traveling the south end of River Road. This is scheduled to continue until mid-July.