Apple's iPad 2 is due on March 2, confirms an invitation sent by Apple for a media event at Yerba Buena Center.

AppleInsider reported that the invitation was inscribed with March 2 calendar date with the side being peeled revealing an iPad. Apple had unveiled its flagship product iPad in the Yerba Buena Center in 2010.

Since the launch of iPad in 2010, hordes of tablets running on Android, Windows 7, HP's webOS and RIM's QNX have been released. Apple has spearheaded the tablet march and has set a precedent for others to follow.

However, Apple now has competition from tablets in both 10-inch and 7-inch. While Apple has placed its weight behind the 10-inch display calling it the optimum size for a tablet, tablets in the 7-inch form are in the market to disprove Apple CEO Steve Jobs' observation. The Register reported that Jobs in an earnings call in October 2010 said that a 7-inch display was less than half the size of iPad's - isn't sufficient to create great tablet apps, in our opinion.

A barrage of tablets donning 7-inch displays started inundating the market after Samsung launched its Galaxy Tab. Some of the key players in the 7-inch segment are HTC Flyer, RIM PlayBook, Dell Streak 7,Samsung Galaxy Tab and ASUS MeMo. In the 10-inch category Apple competes against Motorola Xoom, HP's TouchPad, LG Slate, Notion Ink Adam and Samsung Galaxy Tab.

Here is a list of top 5 tablets in the 7-inch category that Apple's iPad 2 has to fend: