It also means your bot’s place on the ladder is no longer solely determined by the ELO of your bot. Instead, it is sorted by rank and then ELO. Usually there won’t be a difference, but if a bot changes ranks, it could.
Now, you could try shooting for the stars. But believe me, bot development is a lot of hard work. It also is a lot of fun - but I suggest you try to reach the next rank first. Even bots in the lower tiers are beating the in-game AI without breaking a sweat. So beating them with your own AI is an achievement!
For the actual rule update, check the Ranking section of the rules.