Hi Bravo,
You had me worried for a moment
The 2007 supplement you quote states that:
Currently six licensed aerodromes, as listed below, have approved designs for RNAV (GNSS) instrument approach procedures.
Notification of operational availability of these procedures will be through NOTAM action by the specified aerodrome.
Blackpool
Durham Tees Valley
Exeter
Gloucestershire
London Gatwick
London Heathrow
Note that the CAA are talking about "approved designs" for the procedure, not the availability of the approach to be flown. Also see the comment about NOTAM and the lack of mention of some of the former trial airfields e.g. Inverness.
If you had looked a little further through the 2008
supp you quoted you would see that on one hand is says that the NATS RNAV GNSS approaches at EGLL and EGKK will commence from 5 June 08, on the other it states that
Notification of operational availability of the procedures at Blackpool, Durham Tees Valley, Exeter and
Gloucestershire will be through NOTAM action by the specifed aerodrome.
Looking at the current NOTAMS we get:
Blackpool RNAV APPROACHES NOT AVBL
Durham RWY 05/23 GNSS APPROACH NOT AVBL
Gloucestershire RNAV (GNSS) APPROACHES NOT AVBL
Exeter TRIGGER NOTAM on 5th June UK RNAV (GNSS) INSTRUMENT APPROACH PROCEDURES, SUP S11/2008 REFERS
Still looks to me like nothing is available. Whilst the IAP may be available and in your databases it still doesn't mean that its available to be flown until the airports comply with the
Notice to Aerodrome Licence
Holders (NOTAL) 4/2007 specifying the responsibilities and actions required of licence holders intending to introduce RNAV (GNSS)
approach operations.
More than happy to be corrected if my reading of the situation is wrong though...

also good news that we will have RNAV GNSS approaches in the UK from 5th June too
Cheers, Nav.