Online food delivery service GrubHub officially went public on Friday, and quickly became the latest in a series of hot IPOs to explode upward on their first day of trading; the stock closed today up more than 30%. But does the underlying business support the market's enthusiasm?

On Friday's Investor Beat, host Chris Hill and Motley Fool analyst James Early take a look at GrubHub's hot IPO. James doesn't see any real competitive advantage for the company to differentiate it from its peers, but notes that with the huge premium that shares got on their first day of trading, this probably isn't the end of the hot IPO market.

Then, the big debate on Wall Street this week surrounds the world of high-frequency traders, the subject of Michael Lewis' new book, Flash Boys. A story on CBS's 60 Minutes this past Sunday featured an interview with the author, in a segment highlighting the speed advantage that high-frequency traders have over regular investors, and how they can bid up the price of each transaction as it happens, and make a profit as a result. Since the story broke, however, two camps have formed: one in support of the author's case, and the other suggesting that high-frequency trading has, in fact, stabilized the market with increased liquidity, and resulted in a net positive for investors by dramatically narrowing bid-ask spreads. Chris and James take a look at both sides of the argument, with Charles Schwab on one side, and Jack Bogle on the other.

And finally, James takes a look at Veolia Environnement, a French water and sewage company that has seen a run-up of more than 70% during the past nine months. James tells investors how excited he is that "boring" stocks are now getting their day in the sun, and says he still sees more upside for Veolia from here.

Chris Hill has no position in any stocks mentioned. James Early has no position in any stocks mentioned. The Motley Fool recommends Veolia Environnement (ADR). Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.