OK, the results are now in, there were 16 entries in total and the answers given were:
1) Name a line on the London Underground.
3: Circle, Waterloo & City
2: Central, Hammersmith & City, Northern, Piccadilly
1: Bakerloo, Victoria
Other correct answers: District, Jubilee, Metropolitan
2) Name a Train Operating Company that accepts Oyster PAYG on some or all of its services.
3: First Capital Connect, London Overground
2: Chiltern, First Great Western, Southern
1: c2c, London Midland, London Underground, South West Trains
Other correct answers: NXEA, Southeastern
I was unsure about accepting London Underground as a TOC, however it is listed on the NR website
http://www.nationalrail.co.uk/tocs_maps/tocs/
3) Name a LU station that has 8 or more escalators.
5: Waterloo
3: King's Cross St Pancras
2: Bank/Monument
1: Canary Wharf, Canning Town, Euston, London Bridge, Oxford Circus, Southwark
Other correct answers: Bond Street, Canada Water, Embankment, Green Park, Liverpool Street, North Greenwich, Piccadilly Circus, Westminster
A lot of possible answers here so I am not sure why Waterloo was so popular.
4) Name a London bus route that is, or has been, regularly run by bendy buses.
2: 12, 18, 29, 149, 453
1: 38, 73, 436, 507
Wrong (4): 5, C1
Other correct answers: 521, 25, 207
I can't find any evidence of the 5 or the C1 ever being run by bendy buses.
5) Name a place that is featured in the name of three or more London Underground stations (eg if West Croydon, East Croydon and South Croydon were LU stations, then Croydon would be a correct answer).
3: Hounslow, Wimbledon
2: Ealing, Edgware, Wembley
1: Acton, Heathrow, North, Ruislip
Other correct answers: Clapham, Finchley, Harrow, Kensington
One entrant cleverly answered "North". As there is a town in South Carolina called North then this is technically correct.
6) Name a person who has held the Guinness World Record for visiting every LU station since 1 Jan 2005.
3: Ryan Brown
2: Andi James, Steve Wilson, Steven Karahan
1: Hakan Wolge, John Stark, Lars Andersson, Neil Blake, Philip Brown, Rachel Brabbins, Sara Wearn
Other correct answers: Geoff Marshall, Sam Cawley, Antony Brown, Kevin Brown, Martin Hazel
Generally people stayed away from the more active forum members and instead ended up colliding on Ryan Brown. 3 of the 5 entrants who could have answered themselves did so.
7) Name a London Borough that does not have any London Underground stations in it.
4: Bromley, Sutton
3: Bexley
1: Hackney, Kingston, Lewisham
Wrong (8): Orpington, Wandsworth
Other correct answers: Croydon
Wandsworth contains several stations on the District and Northern lines, while Orpington is not a London Borough. Manor House is on the border of Hackney and Haringey but I don't think this counts as being 'in' Hackney.
Name a National Rail station, outside London, that has 8 or more platforms in use.
3: Brighton, Edinburgh Waverley
2: Glasgow Queen Street, Leeds
1: Birmingham New Street, Liverpool Lime Street, Manchester Piccadilly, Newcastle, Sheffield
Wrong (6): Orpington (in London)
Other correct answers: Blackpool North, Bristol Temple Meads, Carlisle, Crewe, Doncaster, Glasgow Central, Preston, Reading, Stirling, Watford Junction, York (+others?)
The obvious answers generally did well on this question, while Brighton was suprisingly common.
9) Name a LU station that begins and ends with the same letter
3: North Acton, Southfields
2: Hornchurch, Kilburn Park
1: Eastcote, Elephant & Castle, Euston Square, Neasden, Seven Sisters, St Pauls
Other correct answers: Edgware, Hammersmith, Ruislip Manor, West Harrow
10) Name a station in Greater London that only has one platform
4: Emerson Park, Mill Hill East
1: Beckenham Road, Belmont, Birkbeck, Heathrow Terminal 4
Wrong (8): Bank, New Addington, Silvertown, Woodmansterne
Other correct answers:
Chesham
MHE was probably the most obvious answer. Several people must have thought they were being clever by picking the obscure Emerson Park, while no-one went for Chesham at all. I am not accepting Silvertown as an answer as the question is in the current tense.
Results to follow shortly