The iPhone 5 launch on Wednesday, Sept. 12, is sure to be the most important event for tech investors this year. The Motley Fool will be hosting a live chat where our top tech analysts will answer your questions and break down what the announcement means for Apple and tech investors everywhere. Be sure to swing by Fool.com at 12:45 p.m. ET tomorrow for all your coverage of Apple's next big announcement.

In the following video, Senior Technology Analyst Eric Bleeker takes a look at gains across Angie's List, Groupon, and Yelp in trading today. As Eric notes, a key catalyst was a "reaffirming" of a price target on Angie's List and also comments from Groupon's CFO over growth in Europe.

However, while headlines might trumpet these news events on the day, Eric notes that all three stocks move together as momentum plays. When a recent Web IPO starts moving in an outsized way, its peers tend to follow. More than anything, that momentum effect looks like a reason for today's gains. In the long run, that just shows the continuing volatility in the space. To see Eric's full thoughts, check out the video. 

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