Chief Executive Tim Cook, presiding over his second major product launch since 2011's voiceenabled iPhone 4S, introduced the highly anticipated third iteration of the tablet, which is available for preorders from Wednesday and will hit store shelves March 16.The highend model of Apple's latest iPa d will be capable of operating on a highspeed 4G "LTE," or LongTerm Evolution, network. At speeds roughly 10 times faster than current 3G technology, that may help banish the sometimes shaky video quality of older devices.Wall Street had anticipated many of the features Cook enumerated on Wednesday, including a higherdefinition "retina display" and a better camera."The iPhone 4S showed us that Apple doesn't need to outdo itself with new product designs to continue extending its domination of a category," said CCs Insight analyst John Jackson. Consumers to pay extra for higherquality video on the go.Andy Bailes of Bowdoinham has been selected to participate in