No more campuses but churches. This is merely a semantic distinction unless the actual nature of pastoral work and responsbilities changes, which is not mentioned (as yet) as being on the table for campus pastors. Merely being "more biblical" in language and terminology does not by itself mean that the infrastructure in place at Mars Hill is automatically more congruent with ecclesiology described in scripture. Ecclesiology wouldn't be so wide and deep a field if everyone could just agree on what "biblical" ecclesiology was. Catholics say we'd all still be Catholics if things were this simple and the Orthodox would say there'd be no Catholics if Catholics truly appreciated this!
My impression of James MacDonald from his conversation with Mark Dever is that he doesn't have conversations, he steamrolls better qualified and more thoughtful preachers. So I can't say that reading that James MacDonald has "helped" Mars Hill on ecclesiology is any real reason to be excited.
Planting new Mars Hill "churches" (campuses) does differ somewhat from planting a traditional church plant if the main goal is to set up a video presentation of a sermon Driscoll preached that, by the time it hits the campus/church will be at least a week old. Unless there's a live feed there may be a set-up in place where the sermons at campuses/churches are what Driscoll preached anywhere between one to two weeks prior. If that's you're thing then ... okay, that's your thing.
What would really be a revolutionary change-up is not calling campuses "churches" but if Mars Hill leadership had the stones to concede they are a denominational network in the making. Ten or more campuses in multiple states would strongly suggest the beginnings if not the actual realization of a denominational structure, especially given the post-2007 by-laws. I don't anticipate anyone at Mars Hill conceding that the church is a denomination until somewhere around 2026.
Now here I must confess one of the reasons I find this development at Mars Hill both quaint and silly is because stressing that Mars Hill in all its heretofore campuses as one church doesn't change what it is or what it has been. The older I get the more I appreciate that the creed says "I believe in one holy, apostolic church". In other words, those of us willing to recite creeds have already been confessing that we believe the Church is one Church. Not necessarily always one in the way we wish it were one (i.e. everyone agreeing with us) but that Christ makes us one despite all the lack of one-ness we see in our lives. A husband and wife may not "feel" much one-ness in their day to day life or when times in their marriage get miserable but that does not mean there is no one-ness there.
I look forward to the day when Mars Hill Church leadership can admit it is a Calvinist Baptist denomination. It's easy to talk about how denominations are fading away or failing and about building bridges but last I checked an egalitarian Arminian is never going to fit into Mars Hill and is certainly never going to get a spot in leadership. The reason denominations grow is not because people "want" to create institutions but because convictions across generations within time and place invariably lead to institutions if the cause survives.
Mars Hill is a few years away from the two decade point. If after two decades and presumably more than 10,000 members Mars Hill leaders can't grant that they're a denomination then they'll be like a fat middle-aged guy who insists he can still fit into his high school sports uniform or wear the school colors jacket. Everyone else can see he can't fit into that stuff anymore but he's sure he can do it with the right belt and maybe not zipping up the blazer. There's no shame in admitting what you have on your hands is a denomination unless you spent so many years talking about how denominations are on the decline that you feel embarrassed being what you talked against
But if they're so certain that this isn't a semantic change then they're welcome to believe it. As I said, I look forward to a day when they can admit they're a Calvinist Baptist denomination already. Right now the only people who seem truly uncomfortable at the prospect of this reality are them.