Originally posted by doops ... but I am taking more and more shots at local indoor events under artificial lighting. ...
What sort of events? If the lighting is bright you will likely be okay with the K-r. Bright lighting helps focus and also lets you stop the lens down for more depth of field.
My experience with my K-r under tungsten/incandescent light is that the closer I'm focusing the more likely I am to get a missed autofocus. Dark museums are challenging for any consumer camera but I'm not bothered by having to manually focus in tricky lighting. Adding to what mpmetro wrote (setting AWB to tungsten helps), using live view can improve tungsten autofocus.
I am very happy with my K-r overall. (Yes, I'm annoyed by Pentax USA's poor response to focus concerns I've discussed with them, but it hasn't limited my use of the camera and I'm not trying to revive this debate.)