At this point I don't read about any actual evidence of the routers being "rigged" from the start. I am watching this closely because I have one of those routers in a home I use. My communications are always encrypted end to end on the computers but the Androids and IPhones are not. Not happy about this report of course. Watching!!!!!
Another good read. For more advanced users (not really advanced just not home owner newbies) a strong mitigation would be to blow away the closed source TP Link firmware and use OPEN WRT, which is tested and has many coders verifying stuff along the way. It is somewhat likely you have a unit that has an OPEN WRT firmware sitting there ready to go online. You would be able to verify the download from their website and be pretty certain its clean and good to go. Their very longstanding reputation is solid and if there is a problem its because dozens and dozens of coders somehow missed it during development -- not too likely. In a sense if TP-Links are under priced simply to gain USA marketshare it could be a boom for you. You get a higher end great piece of hardware for cheap and then flash SAFE firmware from OPEN WRT removing the concerns we are talking about. If you are super "tin-foil hat" and worry about the chips on the boards then you are in a new world of concern. China makes almost all the chips for brands outside of TP Link even the best brands I could name here. For me unless I get proof otherwise I am not going down to the chips on the board at this point. I would feel good about the firmware I mentioned above and would then enjoy the underpriced hardware accordingly. My .02