PastoralEpistles.com

I've been slowly working my way through the introduction to the whole book. I've also read his intros to Titus and First Timothy.

Some notables, in no particular order:

• Witherington posits Pauline authorship with Luke as his amanuensis. He sees a lot of similarities with Lucan tendencies in Acts (vocabulary, LXX influence, style, etc.) but also recognizes the key ideas are Pauline. He says that Luke had a freer hand in the composition of Titus and First Timothy, but Second Timothy has more direct influence from Paul. This summary doesn't do Witherington justice, you should really read it.
• Witherington thinks the order of composition is Titus, then First Timothy, then Second Timothy. I believe PastoralEpistles.com's own Perry Stepp orders them in this way too, though, as I've gathered from papers of his I've heard at SBL, he sees the composition history a bit differently.
• Witherington (as does Towner) also strongly recommends considering each epistle on its own merits, and only thinking about material overlapping in subject matter after this. For example, the tendency to describe the opponents mentioned in both Titus and Timothy is often conflated. Witherington advocates keeping the opponents in Ephesus separate from the opponents in Crete and not discussing opposition generally by picking and choosing references from all over the Pastorals.
• I'm always vascillating on what I think regarding the intended audiences of these letters. I've thought that while addressed to Timothy & Titus, the believers in Ephesus and Crete would've heard the content as well. Witherington, however, sees these as private exhortatory letters. His argument is strong and is causing me to rethink my own perspective on intended scope of readership.

The introductory matter is very readable and well composed. He also has more than a standard bibliography, he actually recommends specific commentaries and monographs and explains why he does so. Very helpful, and it's made me think more seriously about getting the Anchor Bible volumes on Titus (Quinn) and 1&2 Timothy (Luke Timothy Johnson).

That's it for now. I'll likely have more later on this one.