You might also want to check with the professional organizations that oversee your area of study and then look if the US version and the UK version have an agreement to accept a degree from either country.
For instance if you were to study for an MLIS (Library and Info Science) you need to attend an ALA (American Library Association) accredited school in the US or a CILIP school in the UK for your degree to be recognized by the vast majority of employers. A degree from a CILIP accredited school is accepted by ALA and thus employers requiring an ALA accredited MLIS.
Another thing to consider is that while the program may only be a year long you may have to do a year of work related experience before entering a program, rather than having most of the second year spend doing this as is the case in the US. Again in the library example, most universities in the UK require that you have this before you enter the program, and most US universities make this a huge part of the second year, that you are paying for.
If you can't tell, I'm planning on attending grad school in the UK to study library science. Not only is it cheaper (even as a foreign student), but every librarian I have talked to has said that a degree from a school in the UK will serve me better and make more desireable to employers in the US because I will have had an overseas experience and a greater wealth of knowledge from which to draw.
In short, look at the field in which you are studying and ask people in the field what they think.
