It’s one thing to acknowledge that consumer electronics product lifespans are always shrinking, but it’s another thing entirely for a gadget maker to tell you when your new tablet will become obsolete before you even purchase it. The Galaxy Tab 8.9 and 10.1 haven’t even made it off the starting line yet and Samsung’s mobile boss is already spilling the beans on the company’s next-generation devices. Samsung’s J.K. Shin told Dow Jones Newswires in an interview that Samsung plans to release a 4G LTE-equipped version of the Galaxy Tab tablet later this year. He also said that the third addition to the Galaxy S line, presumably dubbed Galaxy S III, will launch in the first half of 2012. We appreciate Shin giving us an insight into Samsung’s product roadmap, of course, but it’s also tricky business. We reviewed the Galaxy Tab 10.1 earlier this month and while we thought it was a solid offering from the Korean consumer electronics giant, it’s a tough sell knowing that a new version with blazing fast 4G LTE compatibility will launch just a few months later.