Thats really what Browser Search and Searcho2k is for

I think it will eventually "get there"... but yep, I'm adding my vote to this :)

but the thing is how much can you control how Outlook instant search works?
because if you're indexing the DB files and the MDC files, you are going to get duplicate results
if you index just the DB files then you lose things such as the folder that it belongs to
if you index just the MDC you can only search part of the content in the MDC

We can control what it indexes, and how.  Under the hood we are called when SearchProtocolHost.exe starts doing it's thing.  

Using an extremely complex set of prisms, and other advanced techniques we can control what gets indexed, and the rest is Outlook displaying what's in the index. :)

so you can have it index something in the db file but have it display the MDC result?

Well, maybe I'm not getting you.  Why would you want it to display the MDC result?

when you search for All Mail Folders in Outlook search, one of the things it does is tell you what folder the item resides in

So an MDC would show "Inbox" or "Sent Items" or something like that
a DB file would show \01\ or what not

Prisms will be extended into the realm of smoke and mirrors.

Seriously though, I'm assured that the theory/idea/principles are already in discussion... implementation of a  product ready change hasn't been timelined yet.

Given the integration we have now, and some heavy work we've been involved in with Engineering and Microsoft in the last 5-6 weeks, we've learnt a TON more about how the whole interoperability works.... so at the moment anything (nearly) is possible :)