Two of the Public Record of Northern Ireland's free-to-access online collections are now accessible via Ancestry as a 'Web' collection. They are the Northern Ireland, Valuation Revision Books, 1864-1933 collection (with both search – by both search and browse options) and the Northern Ireland Freeholders Records collection (a search index with 129,894 entries linked to PRONI's site).
This gives these records, which are currently searchable and viewable in PRONI's ecatalogue, much greater exposure, and should allow an increased number of researchers to gather more information about their Northern Irish ancestors. The Revision Books in Ancestry's collection have also been name-indexed, rather than being searchable only by place, which is an excellent bonus of this latest development. It holds 3,193,180 entries.
Ancestry's 'Web' collection can be searched and viewed for free. You don't need to subscribe or even be registered.
I suspect we'll be seeing some more of PRONI's collection joining the Ancestry database in due course.