The version number means "snapshot of -2 which will be supersedable by -2". It was taken when -2 was in the works and no "ubuntu" was added in the version number to allow superseding with whatever next Debian upload we like (final -2 for instance). I could as well use -1+hardy1 instead next time if this is clearer to you, but I usually use "next Debian rev" + "~hardy1" as it is consistent when I pull a new upstream (most common case).
The version number means "snapshot of -2 which will be supersedable by -2". It was taken when -2 was in the works and no "ubuntu" was added in the version number to allow superseding with whatever next Debian upload we like (final -2 for instance). I could as well use -1+hardy1 instead next time if this is clearer to you, but I usually use "next Debian rev" + "~hardy1" as it is consistent when I pull a new upstream (most common case).