Original Final Crisis artist J.G. Jones has confirmed that he's not going to draw the book's final issue. Instead of Carlos Pacheco, who has been lending a hand starting with this week's Final Crisis #4, however, DC are bringing in a third artist, Doug Mahnke, to draw issue #7. Of course, the book is already off schedule anyway, and even if Final Crisis #7 does come out in February, it's still going to be two months behind.
I find it worth noting that while Marvel were infamously weighing the option of shipping Civil War on time and with multiple artists involved against the option of waiting on Steve McNiven and shipping the book late a couple of years ago, DC are now having it both ways.