Amazon's investment of $100-150 million in Groupon competitor LivingSocial will be announced later today, a source familiar with the situation tells us. All Things D's Kara Swisher reported that the two companies were close to an agreement yesterday. The investment is said to value LivingSocial at "several billion dollars." The news comes as Groupon is reportedly considering a $6 billion acquisition offer ($5.3 billion plus a $700,000 earnout) from Google. An official announcement is expected within the next few hours. Critics of Google's bid have pointed out that the model has very low barriers to entry, with hundreds of competitors. But it's worth pointing out that LivingSocial is the only competitor that has reached a scale remotely close to Groupon's. An industry source estimates that the next nearest competitors -- Tippr and BuyWithMe -- are probably about a tenth the size of LivingSocial. Sursa