Mishra and Koehler have a really interesting take on technology and teaching. I think I read somewhere that if you want to get ahead, you have to get a theory. It seems like they've done just that. Rather, they've expanded an existing theory to explicitly include educational technologies.
I'm pretty familiar with Shulman's construct of Pedagogical Content Knowledge. (In the math ed world, Deborah Ball and a few others have proposed a special domain of teacher knowledge called Mathematical Knowledge for Teaching (MKT) which is located partly within PCK and partly with Content knowledge.) I really liked Misha & Koehler's Venn diagram for PK and CK and how they included a separate but overlapping domain for Technology Knowledge. I couldn't help but wonder if there are aspects of MKT that exist within the sphere of TK or any of the other categories they created. I'm sure there is.
I also couldn't help but wonder if TK is more correctly placed within one or both of the other domains. Is it really a distinct domain of teacher knowledge? Maybe it is. I could go either way on it. Maybe the tipping point for me is that TK is not just about knowing about and how to use both traditional (black/white boards) and advanced technologies (computers/mobile devices) but is also about the ability to learn about existing and emerging technologies. When we started to introduce Interactive White Boards at my school, there were more than a few teachers who resisted them and complained loudly that the IWBs were placed in the center of the existing white boards essentially removing at least 1/3 of the board space. I liked the idea of the IWB but was also wary about its location in the room. Now, I am so glad that my principal had the foresight to put it front and center in the classrooms. I cannot imagine teaching without an IWB now. Many of the same teachers never really explored what an IWB can really do for your instruction. Students used to marvel at things that I did on the board; things that seemed routine to me but that other teachers hadn't tried to do.* I always figured that I couldn't do any permanent damage and that I should just try some stuff. We used to characterize that kind of attitude towards technology as being a "digital native". Mishra and Koehler conjecture that it's part of a special domain of teacher knowledge. Perhaps it is.
One anecdote can't make a theory, but it might provide a little evidence that maybe TK is just part of what we do as teachers. Teachers with better / more developed TK or TPCK can use all sorts of technologies better or more flexibly. They can also adapt to new technologies faster because they have that kind of disposition. And maybe they even seek out or invent new technologies when existing ones can't do what he/she wants. It's certainly an interesting construct and I'd like to learn some more about it.
*Kids used to marvel at the IWBs. Nowadays there's a lot less awe. I think its because the crop of students I have now have had IWBs for pretty much their entire school career. It's hard to get excited about something that's been part of your routine for 10 years.