Yes, changes have been made. libow now support overdrive, lets you specify pullup durations, and will defragment big return APDUs. And small ones, for that matter.
One test script that I use frequently (well, the only one that I have), which, via a couple of dozen invocations of jibapdu and a loadapplet loads a stonkingly big applet onto the iButton and plays with it, went from a run time of over 3 minutes to 40 seconds.
We are cooking with gas. But there's still no documentation.
Approach at your own peril. In fact, the only reason you should be here is if you have a sick fascination with having the full functionality of keymgr available to you, or you're on a 64-bit platform like mine and have had as much luck getting DalSemi's example code to work as I have.
I'll leave you with wise words that I first heard from Ian McKellar, a long time ago.
If your development tools don't suck, you're not on the bleeding edge.