Well, since the rails mailing list idea was rejected, and since I
avoid IRC while at work, and I can never remember to recheck wiki
postings, I'm posting here. Yell at DHH if you don't like it. 
To stay in touch with the wiki, I recommend looking into RSS. Nobody can stay on top of a wiki by hand (or at least, I wouldn't want to). RSS is proving a major benefit to the wikis of the world.
Plus, couldn't you somehow then take advantage of DBI's extra
features, like XML/XSLT/XSQL stuff?
What am I missing?
Rails actually started out using DBI, but to get the functionality I wanted, I had to redo a bunch of things on the Rails side that was already being done in DBI. And when I started doing some performance testing, this double work proved to have a overhead of about 100%. So at least for the MySQL adapter, I thought about how hard it would be to do my "own" adapter to MySQL-ruby.
It proved to be remarkably easy. I think the adapter is around 80 lines of code or something. Then Luke Holden did the SQLite and PostgreSQL adapters in a few hours and that was pretty much the end of DBI for Active Record. It was just too easy to do local adapters that didn't have any of the DBI overhead and could do things the way Rails needed them to be done.
Also, I think to keep my dependencies at a minimum. Active Record is pretty self-contained. It even includes the Ruby-based Ruby-MySQL adapter. So you only need to add the C-based bridges to get going with other databases.
But. With all that said. It's not that I think DBI is a bad project or that I would mind having a DBI adapter. DBI is great and if anyone would rather do a DBI adapter than a set of local ones, I'd be happy to accept it into Rails.
I am, however, concerned that doing a generic DBI adapter might conflict with the auto-incrementation required by AR. There was talks about how it was pretty hard even for ODBC.
Do my preference is for local adapters, but I would be willing to accept a DBI adapter while those local ones were being made.
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--
David Heinemeier Hansson,
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