We have been able to display text for awhile now (see "titty" in the "eink algorithmic art scripts" thread. The holdup is a touchscreen keyboard, and I was working on mine again last night.
I finally have a satisfactory keyboard (with transparency) that I can overlay on video without causing the eink display updates to switch to a slower mode that causes too many update artifacts in the video.
Also, in the new 5.1.0 firmware with broken eink structures, although I was successful getting full-screen updates working in my newest gmplay release, everything I tried (so far) cannot get region (partial screen) updates working on 5.1.0, and they were important for fast text updates in myts on the K3. On the K5 they may not be as important though because the updates are asynchronous (ioctl() returns before the update is complete).