One of the most obvious differences I faced when I moved from LMAX to 10gen were the working conditions. I don't mean like being deep underground in some dangerous situation vs being pampered by beautiful slave boys and girls. What I mean is that the working practices at one company necessitated being in the office for core hours, and at the other flexible hours and remote-working are practically mandatory.
After the acquisition of a company with offices in New York, I pestered my company outrageously until they got fed up and finally relented – they agreed to send me to the US.
To ease the transition, I chose to move onto a project which would allow me to start working in London and continue on the same team after I had moved to New York.
In the extreme over-excitement that followed my relocation, it took me a little while to realise that effectively I was an offshore resource, no different really from any of our Indian test team, and the team needed to manage this appropriately.
I learnt a number of lessons whilst playing this game. Some of these points are also valid for teams with remote resources (e.g. people working from home).