NEW YORK ( TheStreet) -- When it comes to Lending Club, membership may -- or may not -- have its privileges. "I am very supportive of this company," said Peter Renton, CEO and founder of Denver-based Lend Academy, an industry information and training organization aimed at the fast-growing peer-to-peer lending market. "But I still feel the management is missing an opportunity to properly explain what the investor opportunity is for the long term." Renton, a blogger and author, has written a book called The Lending Club Story about how, starting in 2007, a consumer lending unknown named Renaud Laplanche grew to harness more than $2 billion in investable assets and attract backers such as top-tier VC firm Kleiner, Perkins, Caufield & Byers; former secretary of the Treasury Lawrence Summers; and Google ( GOOG). "The attraction is clear. At its heart, peer lending is a fabulous new asset class for both investors and consumers," said Andy Dull, managing partner of Twin-Engine Consulting, a Richmond, Va., consumer lending consultancy that has done work at Lending Club. It also never hurts that there are whispers of a massive IPO for the ticker, probably next year. What's Lending Club's secret? It cleverly uses the Web to flank traditional Wall Street lenders by connecting directly those with money to lend to those in the market to borrow. I am not ashamed to admit I was impressed when Lending Club COO Scott Sanborn confirmed to me in an email that investors saw roughly a 6% annualized returns, net of fees, not only in 2008, but also 2009 and 2010. If you remember, friends, that is when traditional banks paid nothing. "I am very proud of the performance of the platform during the worst downturn in 75 years," company founder Laplanche told me last week. But several months ago a slow and steady drumbeat of concern began flowing my way over how investor returns are disclosed at Lending Club. Back in May, Allan Roth, an analyst I trust, wrote at CBS MoneyWatch that his test investment of $2,600 gave him returns much lower than expected.