Adding a new column now does seem disruptive, but I also really would like to see if we can start gathering that data somehow. There are 5.5 digit DMMs that can compete with a 6.5 digit DMM in certain conditions, for example.
Would it make sense to put the counts that we have as a note on the digits entry for the time being? Then at some point it could be made into another column.
Another topic to discuss is how to determine the counts. If the DMM is physically only able to display 1,999,999 do we consider that the counts or round up to 2,000,000? I have also seen some oddities especially with handheld DMMs, where everywhere it is stated as a 50,000 count but is actually 55,000 or 52,000. So we have the concept of "published" vs. actual in some cases.