Well, it depends. Is your wife going to be working or not? If she's then should be enough. I explain:

A decent 1 bedroom flat in central london will cost you about 1,500 per month, so about half of your income. Check www.findaproperty.co.uk for prices of rental property as well as buying. In any case you will need to spend in transport and so will your wife unless you walk work and you never go anywhere so let's say that will be between 100 and 50 per person depending on how much you use transport (a normal travel card zones 1 and 2 is about 100 per person). Bills are quite cheap if your flat is well insulated etc. then calculate about 200-300 in bills , extras 100 ? that leaves your roughly about 1,000 pounds. Food for two about 400 (forget anything fancy and not too many fruits and vegetables as you will pay about 1.5 USD for a decent tomato (one tomato). That leaves you about 500-600 for two people. If you want to eat out calculate no less than 35 pounds per person in a cheap place...no wine no dessert just a drink and a coffe one course only. make your own calculations.... cinema between 7- 12 pounds. A night out...well keep adding. So if your wife is planning not to work FORGET IT. If she works, it should be fine as she will be contributing to rent and her expenses. Do no expect to save much. London is not so glamorous as one may think unless you earn over 85,000 per year before tax. A mortgage lender for example will only lend you about 3.5 times your gross salary (see prices of flats on the site above) so more or less have an idea what you need to earn. So basically that money will not be enough to have a quite normal decent American style life in London. Anywhere else in Europe (maybe with the exception of Paris and the Scandinavian capitols) you should be much better off as an expat. So evaluate carefully.
If your wife works that will add at least 25-35 gross more per year (minimum) to your total income so you will be in about 80,000 between both. That should work out fine as you will be able to save all of your wife's salary or have a better quality of life. Any more specific questions feel free to ask.
Regards,
Gonzalo