Opportunism is a Silicon Valley trademark, so it should come as no surprise that Google (NASDAQ:GOOGL) is after a larger chunk of PayPal's lucrative business. The search king is dropping Checkout to focus on Google Wallet in the wake of losing key staff in its payments group.

Google introduced a number of updates to Google Wallet at last week's I/O developer conference, including a mechanism for sending money via Gmail and storing payments credentials securely in Chrome. eBay (NASDAQ:EBAY), meanwhile, continues to dominate, with PayPal's net volume increasing 21% to $41 billion in the latest quarter, says Tim Beyers of Motley Fool Rule Breakers and Motley Fool Supernova.

Investors are nevertheless unnerved: Shares of eBay stock are up just 3% since the last earnings report versus a 6% gain for the S&P 500. Efforts to disrupt PayPal are likely taking the biggest toll. Google's ambitions won't help, but PayPal is also an enduring brand. Don't sell eBay stock if you own it, Tim says, and add it to your watchlist if you don't.

Do you agree? Please watch to get Tim's full take, and then let us know whether you would buy, sell, or short eBay stock at current prices.

Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team and the Motley Fool Supernova Odyssey I mission. He owned shares of Google at the time of publication. Check out Tim's web home and portfolio holdings or connect with him on Google+Tumblr, or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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