It might be splitting hairs, but I wouldn't say barbel are the new carp; it's more that some barbel anglers are the new carp anglers, and even that's probably unfair to those carp anglers who fish with flexible ingenuity. Barbel remain barbel, and you don't have to join the midnight floodbank car park and tented village to catch them. It's great to have good barbel fishing in the region, but nobody's obliged to get fixated on doubles, and I've caught them on every method except carbelling, float, leger, free-lining and pole included. I last weighed one three years ago because it looked suspiciously big, but my scales batteries ran out long since.
Barbel distribution is not only a north/south thing. Of the five rivers I can call reasonably local, only one has lots of barbel, and these are localised to the lower middle and tidal of a very long river. Neither the tributaries that drain the Peak District nor the lowland ones offer much viable barbel fishing and that's been the case for a long time. Along with a fishing friend, I recently stumbled on a video where an angler night-fishing one of these trib's caught barbel of 7, 12 and 15 lbs - an outstanding and well-deserved catch. The 7lb-er was the exciting fish, we agreed. When there are only doubles left in your river, you've got problems.
I like the French situation as reported by Clive and Steve. Plenty of barbel - and other species - and license to roam in all kinds of romantic, picturesque and lightly-fished rivers. Who cares if the barbel seem to top out at "only" 9lbs? What kind of "only" is that? It's said that where I fish for them these days, one barbel in four is a double. But I don't enjoy it any more or less than when I first caught three and four pound barbel on the Severn in the 70's. Or fish of 5 or 6 pounds on the Dane in the 90's. Or, at the start of a short-lived barbel boom in the 00's, dozens of 1 -2lb barbel per session on the Welsh Dee.