In summary, I loved every minute of it - with the exception of every one of the team getting their credit cards cloned within a week of arriving (solution is to either pay for everything in cash, or get your bank to call you every time there's a charge on it).
Hotels are expensive - £250/night for a PremierInn equivalent, but we got apartments instead which were about half that price for a 2 bedroom apartment near the casinos & night clubs (Smolenskaya/Arabatskaya area).
There are tourist supermarkets (Marks & Spencer prices), local supermarkets (Tesco prices) and plain old street markets (prices differ on how close to the centre you are - so if you get a train 30 minutes outside of Moscow you'll pay £5 for a week's shopping, but you'll need to be able to speak a little Russian to get by).
Language can be a problem, as you can't even try to say the words by spelling them out, due to the use of the Cyrillic alphabet, but after a month you start to recognise/read signs/notices - doesn't help with the speaking/listening though. The 'tourist' areas will have at least one member of staff who speaks decent English, but don't rely on it, and get used to pointing at things on the menu.
Don't assume a shop that looks like a 'western' brand (even down to the name) is actually the same company, as they've got no qualms in using someone else's branding to further line their own pockets.
Most places are within walking district - our office was next to the Kremlin (although lots of western businesses are based just east of the centre, near the main train station from the airports), and the drive took 30 minutes in traffic to cover the 2 miles to the apartment in Smolenskaya (near the old Science Ministry building).
Plenty of nightlife & good range of restaurants, and lots of places open all night - with nice ladies
- although the Boarhouse is a favourite of ex-pat workers and has a choice of locals and Asian ladies if your into that sort of thing. Don't be surprised if you see a girl from the office 'working' elsewhere in the evening. The salaries for the locals are getting better, but there's still a low-paid mass out there who need/want to supplement their incomes. Just be direct and say you're not interested and they'll move on, but on some nights you can't even get to the bar/loo without going through 4+ rows of ladies waiting for their marks.
The Metro is very cheap, but can be confusing as the characters they use for the station names changes for modern Cyrillic to old Cyrillic seemingly randomly, so despite you learning one 'name' you may not see it
Also don't try to get on a Metro when the doors are closing as they won't reopen and close with a much greater force than they doors on the Tube do. You'll have to be forceful when getting on or off as otherwise you'll be left n the platform or train as the doors close.
Weather is usually quite good, and doesn't seem to flick from wet to dry and back every hour, but tends to follow the proper seasonal warming & cooling. However the extremes are greater than the UK, with upto 40ºc in summer and -30ºc in winter.
Sightseeing is the main leisure activity. There are a fair few museums and art galleries with walking distance of the centre, and even some tours of the KGB/FSB offices, but if that doesn't float your boat you can go swimming, skating, shooting, ski-jumping, or go to the fair ground at Gorky Park (walkable from Oktyabrskaya, Shabolskaya or Leninsky Prospect metro stations).
If you are walking, do not try to cross any road that's got more than 2 lanes each way, as the locals will make use of the inter-lane gaps as 3rd & 4th lanes and you won't spot them. If you see a black car with a blue flashing light on the roof then get out of the way, but make sure to look both ways right across the road as they will use whatever space they can find to get through. The blue light doesn't mean there's an official in there or that there's an emergency - it's just that some of the well-off like VIP status and pay a fee to do so, which includes the right to use the blue light.
Don't be shocked by the state/quantity of top-end motors either, as it's like Kensington, except they'll park their Veyron on a 12" high kerb
Anything else you want to know, just ask.
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