But how unstable is Flash really?

You probably read that  Steve Jobs officially declared Flash a stability nightmare and that Adobe’s CEO responded that OS X is to blame. Hard to take sides in this blame-game, especially without access to Apple’s crash reports data. We do, however, have access to Mozilla’s crash-stats.mozilla.com. Could those figures provide us with at least some relevant statistics about Flash’s reliability?
I imported this csv-file with the top 300 crashers for Firefox 3.6.3 for the last 50 days (3.6.3 was released on April 1th) into a Google Docs spreadsheet and counted the number of crashes for each line where “Flash” or “NPSWF32” is in the signature (SUMIF without wildcard characters, seriously Google!?). You can find the spreadsheet here, but these are the results:

total number crash reports for top 300 crashers:3583582
crash reports with “NPSWF32” or “Flash” in signature:1154488
flash-related crashes %:32.22%

That’s right; almost 1/3 of the Firefox 3.6.3 “top crashers” are clearly related to Flash! So yes, there is good reason to consider plugins in general and Flash in particular a stability risk for Firefox. And for the record, the numbers for Mac seem to indicate that the problem is even (much) worse there! So hurray for Firefox 3.6.4 with Out of Process Plugins! And hey Adobe, get your Flash together!