Just a few comments. The London prefix was added to the Wasps professional side's name in 1999 to differentiate the pro club from the continuing amateur side Wasps Football Cub who have just won Middlesex/Herts 1. It is similar to the way that Sale were remained Sale Sharks and Gosforth were renamed Newcastle Falcons. See.
In terms of the drop off in support there has been a general dissatisfaction with Steve Hayes since he took over in 2008. This culminated in the mishandling of the season ticket renewals for the 2011/12 season when the prices for the best seats, where many of the older long term supporters sat, were massively hiked by 20% or more.
That increase effectively lost the club about 1,500 season ticket holders. The base crowd therefore dropped from about 7,000 to something more in the region of 5,500.
Going forward it is vital, absolutely vital, that the club move back to West London to a ground suited to rugby and well connected to the London Transport network. The lenient interest and support for the club is substantial, bigger than both Irish and Sarries, and I have no doubt with the right location a mid table Wasps side would get a regular crowd of 10,000. Out of the likely options on the table moving to a new ground at either Barnet FC's training ground in Harrow or sharing the proposed Brentford Community Stadium near Kew Bridge are the best options in my book.