In the Action Editor, sliders are now drawn beside IPO-Curve and Constraint Channels and for the active Action Channel when the 'Show Sliders' option in the View menu is turned on. This behaves like for shapekeys. You can change the limits of the sliders by either Ctrl-Clicking or NKEY over the name of the relevant IPO-Curve channel. Also, documented the IPO-curve struct a bit. There are a few variables there that I'm not sure what they are used for.