Confirming speculation from earlier this week, PopCap Games announced this morning that an enhanced iPad version of its smash hit casual game, Plants vs. Zombies, is not only in the works, but now available to purchase from the App Store.

When iPad owners begin hitting the App Store en masse tomorrow, they'll find Plants vs. Zombies HD to be an enhanced version of last year's Mac and PC favorite, which lets you battle back waves of comically-designed zombies using various offensive-minded plants. Plants vs. Zombies contains the entire 50-level campaign in both Adventure and QuickPlay modes, as well as the Survival mode seen in the original Mac/PC release. Moreover, the iPad version includes four new unlockable achievements (for 17 in total), as well as 18 mini-games, including newcomer, Buttered Popcorn.

Created exclusively for the iPad version, Buttered Popcorn lets you attack zombies by first buttering them up with a touch. Up to 11 zombies can be buttered at the same time, at which point they'll display a pat of melting butter atop their rotting noggins. After that, you can launch corncob cannons in their direction, triggering an explosion of popcorn upon impact. You can clearly see the Buttered Popcorn mode in action in these debut screens, which demonstrate how sharp the hand-drawn game should look on the iPad's 9.7-inch display.

"The iPad is a fantastic platform for gaming, and Plants vs. Zombies HD allows us to show off the great new features and functionality of this exciting device," said Andrew Stein, PopCap's director of mobile business development. "In this adaptation, we've focused on the iPad's multitouch capabilities and opportunities for new gameplay like the Buttered Popcorn mini-game that will excite both new and current players."

Plants vs. Zombies HD is now available to purchase from the iPad App Store for $9.99. The iPad version follows the successful iPhone and iPod touch iteration, which launched earlier this year to strong reviews and sales, racking up more than 650,000 total downloads since February.