Plants vs. Zombies for iPhone [$2.99] and iPad [$6.99] both received some content loving while you were in bed last night. Plants vs. Zombies iPhone received Vasebreaker Endless mode, which packs in a total of nine levels. The iPad version, on the other hand, now supports Zen Garden, Vasebreaker Endless, "I, Zombies" mode, and four new mini-games: Slot Machine, Portal Combat, Beghouled Twist, and Zombiquarium have been included. The Plants vs. Zombies wiki has delightfully ridiculously in-depth looks on each of these modes, if you need to know exactly what you'll be getting into before updating.
It's notable that PopCap is continuing to push the free-to-play aspect of Plants vs. Zombies mobile. As Kotaku reports, only the first levels of Vasebreaker and I, Zombie are available from the get-go. The rest of these game's respective levels, and the other mentioned modes, need to be purchased with in-game coins, which of course can be earned or purchased straight-up.