Bitmap indexes?

One of the reasons why I originally stated following the hackers list is
because I wanted to implement bitmap indexes.  I found in the archives,
the follow link, http://www.it.iitb.ernet.in/~rvijay/dbms/proj/, which
was extracted from this,

http://groups.google.com/groups?hl=en&threadm=01C0EF67.5105D2E0.mascarm%40mascari.com&rnum=1&prev=/groups%3Fq%3Dbitmap%2Bindex%2Bgroup:comp.databases.postgresql.hackers%26hl%3Den%26selm%3D01C0EF67.5105D2E0.mascarm%2540mascari.com%26rnum%3D1,
archivethread. 

At any rate, that was some number of months ago.  I've started looking
at the results posted from their bitmap GiST efforts and found that they
were being tested rather poorly to be of real value (I also found it
annoying that the project seems to quote other people's work without
giving credit).  Nonetheless, I thought I'd post to find out if anyone
feels there is still a need for this?  That is, I'm not really sure that
data warehousing or DDS systems are currently very common with Postgres.

If the group here still see value in adding various types of bitmap
support, can someone please point me to some documentation.  I had
several bookmarked but lost then when X crashed.  Anything that outlines
cache strategy, index support, am overview, and any other documentation
that would help excel my understanding of the code as well as the
various structure relationships would be wonderful?

Oh yes, one last question, is the required method for adding index
support via GiST?  I ask because it seems to me that inserts could be
exceptionally expensive, though as usual, I still have more to look at.

Thanks,Greg


P.S.  And yes, I have been reading lots of code...including
walk-throughs!  :P