oh..also..given you will be buying monthly cards, I highly recommend you register your Oysters

Thanks luckykat. I'll definitely come expecting to get a photocard for my son, and we'll definitely register our cards so we don't lose all the £ we've put on them should we lose the cards, especially since I can almost expect as much from my 6 year-old! Thanks again for your assistance. We're looking forward to our 3 months over there.

Just got back from London today and used oyster for my 7 day zone 1 & 2 travelcard (unfortunately they no longer offer the 7 day zone 1 card) and I want to tell you, it was easy, quick and efficient.

To get to Heathrow from central London, I had to add a prepay to the card....the oyster supplement to the zone 1 & 2 for a trip to Heathrow was £1.80 weekdays after 7 AM and would be only £1 outside of that...wow it worked great as I said.

The biggest pleasant surprise was they didn't even charge me the £3 deposit the literature speaks about and now I really understand the concepts involved with it and it is easy!

Great--thanks for your report. I'm definitely going to Oyster it! We leave in 17 days (got pushed back a bit).

samtraveler, re your question, "when I get my Oyster do I need to bring a passport size photo, or will my old photocard suffice?", I was also confused about the whole photocard thing, so I searched the TFL website and found the rules on when photocards are needed at http://www.tfl.gov.uk/tfl/fares-tick...ds/index.shtml

Here's what that page says about whether adults need photocards:

You do not need a photocard to buy and use any adult rate Travelcard or Bus Pass on Oyster.

You do need a photocard to buy or use:

monthly or longer period Travelcards that include validity to a National Rail station beyond Zones 1 - 6 (not needed Moor Park to Watford/Chesham/Amersham inclusive);

monthly or longer period Tube only point to point season tickets (between stations in zones A-D);

7 Day, monthly or longer period National Rail only season ticket.