Retroit you're very wrong. Roundabouts are far more efficient for 4 way intersections than lights or stop signs. They allow more cars through with fewer waits. They are far safer.

From http://www.iihs.org/externaldata/srdata/docs/sr3505.pdf
Researchers
at Ryerson Polytechnic University, the Institute,
and the University of Maine studied
crashes and injuries at 24 intersections before
and after construction of roundabouts.
The study found a 39 percent overall decrease
in crashes and a 76 percent decrease
in injury-producing crashes. Collisions involving
fatal or incapacitating injuries fell as
much as 90 percent.
These findings are consistent with those
from other countries where roundabouts
have been used extensively for decades.
They also are consistent with preliminary
studies of U.S. roundabouts.
The safety benefits don’t come at the expense
of traffic flow. In fact, where roundabouts
replace intersections with stop signs
or traffic signals, delays in traffic can be reduced
by as much as 75 percent.
They are not a trend. They are the future. While not appropriate for every intersection they eliminate many of the problems associated with intesections. Expect to see many more intersections replaced with roundabouts.