So far you still can use a seblod form for the generic search.
We developped a text field plugin which is ajax powered so that when you start writting in the field you get the automatic suggestions from the title, introtext and fulltext of any content. This is the Autocomplete field plugin we are now using in our projects.
We may put it for download when the market is open for third party contributor.
Instead of putting the CCK field in the RESEARCH tab of the form (because you don't want to search on only one content type, we then just put the autocomplete field and... voila!
This new generic search produces right rewritten sef url when the smart search (com_finder) only produces wrong ones unless you add hidden menu items.
cyril