As someone living in a country where , is used as the decimal separator, I cannot begin to describe the number of times CSV data has caused me grief. This becomes especially common in an office environment where Excel is the de facto only data handling tool that most people can and will use. Here the behavior of loading data becomes specific to the individual machine and changes over time (e.g. when IT suddenly forces a reset of MS Office application languages to the local one).
That said, I don't really know of any alternative that won't be handled even worse by my colleagues...
