Hi David,
It seems from a little search I've just done on this site (http://www.growsonyou.com/question/show/10272-gooseberries-or-should-say-no-gooseberries)
and also on the Allotment and Veg Gardening forum (http://chat.allotment.org.uk/index.php?topic=60121.0)
that they may well take a few years to fruit if new, also that they benefit from a potash feed in Feb/March. Too late in the year to do that now. I was interested bcos ours have also been feeble, sadly. Mildew is a common problem, but I bought a mildew-resistant one, and after one year of some moderate fruit, last year all the leaves disappeared and the plant died! Our other bush is too much in the shade I reckon, so I'll try moving it. It looks fine and healthy, but no fruit...