I must say, I'm very worried. The H2G2 movie was dreadful and I'm not sure Colfer can pull off the Hitchiker humour. Even Terry Pratchett would have been a better choice. I'm also a little jealous, because I'd always dreamed of writing the sixth book. Obviously I knew it would never happen, but that doesn't mean I have to accept it.
I'm curious to see how he's going to save the heroes from the Vogon Constructor Fleet at the end of Mostly Harmless. Of course, they could just hope the Vogons still have Dentrassi onboard and hitch a ride. Or Colfer could go the route of the fifth radio series, where the babel fish shift their hosts into an alternate dimension. However, I never bought that excuse either.
Only time will tell, I guess. But here's advance warning that I'll hate it. And complain. A lot.