It's not surprising to me, really. The Roman Catholic right has been deeply involved in the development of the theocon movement from the beginning, with the likes of Neuhaus and Robert George providing the main intellectual background for much of theoconservatism. Really, Catholic conservatives have been involved in this for quite some time -- after all, Paul Weyrich (a Melkite Catholic deacon) helped set up the Christian Coalition, and has been a mainstay of the theocon movement and social conservatism in general.
I would say that the theological disagreements between conservative Catholics and evangelicals remain, but the idea behind movements like this is to leave those disagreements on the level of theology, and rather band together over issues that conservative Catholics and evangelicals agree about -- relating to the "culture" -- and try to get things ionm the culture and law changed to reflect those views. It's more of a coalition of convenience, the idea being that banding together and working together more can be achieved than working seperately. But it's certainly true that the right wing of the Catholic Church in the USA is definitely a part of the "religious right", not just in sympathy, but in actual fact in terms of what certain individuals have done and continue to do, their involvement with the neoconservative political movement and so forth.