Here is the Top 10 external bugs of Flash Runtime in Feb 2012, which is order by incoming votes in Adobe bug base:
1. choppy audio and video on xoom with android 4
https://bugbase.adobe.com/index.cfm?event=bug&id=3099866
2. 11.1.102.62 and Win2K install – SetDllDirectoryW not supported
https://bugbase.adobe.com/index.cfm?event=bug&id=3120661
3. Mac OSX Player Issue: kernel: IOSurface: buffer allocation size is zero.
https://bugbase.adobe.com/index.cfm?event=bug&id=3077658
4. Use of * type causes memory to explode (without any instantiation of objects)
https://bugbase.adobe.com/index.cfm?event=bug&id=3123526
5. List / Button components not rendering properly in Chrome / IE
https://bugbase.adobe.com/index.cfm?event=bug&id=3121222
6. Way bigger app file size once app is published
https://bugbase.adobe.com/index.cfm?event=bug&id=3014058
7. Problem with Clipboard on iOS
https://bugbase.adobe.com/index.cfm?event=bug&id=2927055
8. En Firefox Flash Plugin does not send referer to Flash media streaming server – SWF Verification and referer check fails
https://bugbase.adobe.com/index.cfm?event=bug&id=3117684
9. Flash 11 showing black shapes in BBC iplayer (fixed in internal build)
https://bugbase.adobe.com/index.cfm?event=bug&id=3008910
10. Consistent App crash for Flashplayer 11.1.102.62 (NOT 11.1.102.55)