Rideshare matching, while an important function in most metropolitan areas, isn't seen as all that important by some. Databases are small in most areas. Placement rates are debated. And, over the past few years, additional matching services and capabilities have arrived. Witness Craig's List, erideshare, and more.
It is likely that no matching system in place 15 years ago is in operation today. No vendor of ridematching systems operating then is offering a matching system or service today as far as I know. (This statement is probably true for a shorter time than suggested here.) What may be in place in 5, 10, or 15 years is unknowable but history would tell us there will be high turnover, new services, and faded services.
However, one person matched could mean over 400 vehicle trips eliminated for the following year. The databases can be mined for more results than are typically sought. Spending $200 (or so) in public funds on one placement isn't all that expensive in that light.
Where is the matching function going? Are we going to see lots of small matching systems with capabilities spread even thinner? Are we going to see integration of matching capabilities?
And what of less-than-matchable outcomes? (telecommuting, walking, bicycling, changed work hours, etc.) How should we be treating those in on-line services in the future?