These issues are a major pain in the ass.....In no particular order......

1.)     Non equal weighting of spline tangent length at endpoints, especially out of whack on 2 point spline.

2.)     Erratic behavior of spline curvature when sketching a spline (even more so when sketching around a shape.)

3.)     Control polygon no longer shows all of the CV’s (control polygon points).  When a 3 point spline is drawn in 2010 only 3 CV’s are shown.  In 2008 all 5 CV’s are                  shown

Can Solidworks please stop guessing curvature of splines for me?? It guesses wrong almost everytime.  Making adjustments to correct this is a major workflow slowdown.