[MikeNewYork]

Ozron wrote:

[/quote]Will general misuse transform 'data' into an uncountable noun while 'datum' slips through the floorboards?

That's a great question. I think that is already happening. Scientists still use data as a plural noun. They are focused on data as a series of observations, values, figures, etc. You will hear "These data are very convincing." Others, particularly those in the computer and other information fields, use data as a singular mass noun. In those areas, data refers to a mass of information.