Launchpad helps you to appraise a bug by giving you a calculated measure — called bug heat — of its likely significance. You can see bug heat in bug listings, and also on individual bug pages, as a number next to a flame icon.
Here's how Launchpad calculates the bug heat score:
|Private||Adds 150 points|
|Security issue||Adds 250 points|
|Duplicates||Adds 6 points per duplicate bug|
|Affected users||Adds 4 points per affected user|
|Subscribers (incl. subscribers to duplicates)||Adds 2 points per subscriber|