Between the dense new theme and the original, I go between 18 entries and 26 entries. The original also has noticeably more preview text. The "normal" new theme gives me only 14 - nearly half the number. Were my window a bit shorter, it would be half, because the header area and priority-inbox-label lines are larger.
The increased whitespace makes it massively less dense.
It definitely took me a bit to get used to a typography-centric layout. I really do like it now, however.