Differences I've noticed so far...

• UK buses run in a straight line.  They don't loop around like in the US.  You will get on the wrong bus many times.
• Escalators are organized.  In the US, everyone clogs the step their on without regard for people behind them.  In the UK, you must stand on the right so people can pass you on the left. Very nice.
• Clothes dryers are RARE.  If you have one, it is not a separate appliance. Clothes washers take about an hour per load.
• Wardrobes are SMALL.  Good luck fitting an American-sized clothing arsenal in them.
• A little bit of walking is from one station to another- about 30 minutes total.  A decent amount of walking is several blocks each way and well over an hour.  A lot of walking means you are not taking public transport... hope those heels are comfortable.
• Mobile phones can't dial specific phone numbers...unfortunately that includes most government numbers.
• A pint or two at lunch is not frowned on... it's quite expected.
• Libraries, museums, parks and churches are free to enter, for the most part.
• Times are listed in 24hr format and 12hr format seemingly willy nilly.
• No physical bill exists for a 1 pound note... your pockets are going to get heavy.
• Other immigrants find American accents annoying... Brits seem to find them cute.
• You have to pay 150 pounds per year to watch tv... Netflix it is, our tv is too small to make that worth it.
• American banks will freak out when you start using your card in the UK... doesn't matter that you told them.
• The "W" in Southwark is silent... as is the "h" in Fullham.
• Trash= Rubbish, Boot=Trunk, Bonnet= Hood, Loo/toilet= Bathroom, Lorrie= Delivery Truck
• Prospective employers are VERY interested in your immigration status, age, gender, religion and ethnicity.
• When one is with friends, drinks are bought in rounds...too bad if it is your turn and you're not thirsty.

More to come...