I'm sure there will be Integras next season - Jason Hughes has been after one for a while, and John George will need a new one. They're good cars for independents because they are not too far off the pace, relatively easy to set up and they are built very strong, particularly on the suspension, compared to S2000 cars.
I've heard that Vauxhall can only afford to run 2 cars for Giovannardi and Neal next year, so it makes sense to sell a third car to a decent independant team to mix it with your rivals. The first year Eurotech got an Integra from Team Dynamics, TD were still running Integras themselves and Mike Jordan ran towards the front for most of the season, but I recall on a few occasions he didn't make it too difficult for the TD cars to get past him. I suspect the same will aply with VXR. The only thing is the Vectra is not to every drivers taste - Chilton struggled with it, and Matt Neal didn't have a great season in it really. I think Gio will win it again next season, the BMW's aren't consistent enough.