One relates to offsetting splines (they've started looking at the need to be able to specify an ad hoc definition of the spline past the endpoints, to enable, say, offsetting a pair of splines at an acute intersection).
The other is, I suspect, going to impact rather more on the average user. They've finally decided to do something about the ambiguity we've always had to live with, when a line is tangent to an arc. I'm talking about the way, when a sketch entity is dragged, the line can flip from growing out of the arc (like a car driving out of a turn) to exiting at 180 degrees to the arc direction (as though the car smacked perpendicularly into a wall at the turn exit and bounced back).
This solution makes a mockery of "preserving design intent".
The headaches this caused in coming up with variational sketches involving tangent arcs, especially for tricky stuff like sections through tricky rollformed profiles and such, were at the migraine end of the spectrum. They're now going to capture which solution represents the desired intent. Halleluyah !
Furthermore, circles and circular arcs can now invert (go from convex to concave) Double Halleluyah !
I guess it'll be SldWks 2006 before these make it into the package, unless there's a 2005+.
(If you're a beta tester and know different, just sit on your hands and think smug thoughts)