there is none in the beta, it has never been said that entrenchment would feature a campaign, so I don't think it will. there will be a campaign eventually I guess, but it won't be in entrenchment. I'd say it's in the third mini expansion which was originally planned for summer, but with the current time table I doubt that is realistic. wel'll see. the second one's diplomatic options could also lend to a campaign, but I guess there is enough room in that area alone to fill out even without a campaign.

so, yeah. entrenchment basically follows the formula, you could say it's more of the same. but I think it will be a great addition to the game and some of the new features are great fun already.