These days, people who buy new PCs running windows will be purchasing a machine running Windows 7 64-bit. I don't have strong opinions on operating systems so this seems fine, except Bloomberg's excel API does not support 64-bit applications. When asked they don't give a data at which they'll start supporting it either. So either no one in finance is buying top end new computers that benefit from the 64-bit architecture or only a very small percentage of users actually download Bloomberg's data into excel files for more complex analysis so Bloomberg hasn't felt enough customer pressure to make sure that their product is fully compatible with the majority of new computers.
Either way, it's really weird.