Some notes from a few hours of evaluating htDig....
htDig development cycles seem pretty long too. 3.2.0b2 in April 2000, and 3.2.0b3 in February 2001. I can't figure out which one of these three projects doesn't need CPR.
htDig is cgi and C++ based. It builds under Red Hat 6.1 w/o needing the upgraded libraries that Swish++ needs.
It does excerpts automatically, so from that aspect may be a better choice for folks that want excerpts than either SWISH projects. You can feed it from external processes, but at first glance that may make for a very very slow indexing. I may experiment with that.
It does stemming as do the SWISH engines, but has no explicit wildcarded searches.
