And I'm really not interested in Groupon
Despite LinkedIn's very successful IPO, I don't believe that there is a general bubble in technology stocks. Some are undervalued (I think Cisco and Apple are among them). Many are about fairly valued, so I'd hold them if I owned them but wouldn't buy them. And, as in any industry, some are overvalued. Earlier, I stated that I thought LinkedIn had a viable and scalable business model, and that it had a defensible competitive advantage in its niche. However, LinkedIn is way overvalued, in my opinion.
Groupon just filed for an IPO, and given the investor interest in the company, this IPO is also likely to be overvalued. Morevoer, I don't think that Groupon really has a competitive advantage - as this Morningstar article argues. Social media is the next hot thing, but I do expect many of the IPOs to be way overvalued. I think that Facebook and LinkedIn are two I'd invest in at the right price, but I think that from here, Groupon's relative fortunes may actually decline. At the very least, competition is going to be stiffer.