Last modified: 2011-03-13 18:06:24 UTC
In contrast to minor edits, sometimes people would like to lark it's edit as an Major edit (M instead of m perhaps). Those kins of edits could be emphaised in the watchlist indicating that a lot has been changed.
If it's not minor, it's major. It's all advisory anyway, so don't take it too strongly. Your edit summary should usually reflect what you changed.