I believe if the excel cells have a defined type, you can use the Range NumberFormat property node to return the formatting (i.e. a date code would be mm/dd/yy hh:mm:ss, text would be text, numbers would be "0.00", etc.). I'm not sure how involved it would get if they're left as General.
I modified the Write Table to Excel.vi example that comes w/ LV to show what the returns look like (LV 7). The cells' formats are undefined, so it just returns "general".
ETA:
The subvi's should be in:
C:\Program Files\National Instruments\LabVIEW 7.x\examples\comm\ExcelExamples.llb
Message Edited by Jonnie 5 on 12-07-2005 02:31 PM
2006 Ultimate LabVIEW G-eek.