There are only 3 good reasons for company acquisition: to buy user base, cheap idea or technology that takes time to recreate.
I think that Groupon is the fast answer to social demand based on recession that warms up because of the attention it is getting. And once the recession is over, and people calm down there is much less attention to such companies. But current price is heavily overrated due to above-mentioned reason.
Recreation of Groupon
Google has everything to create almost any software and make it popular: Brand, Users base, and Money.
How much does it cost for Google to create some initial version within 2 months using average salary rates from Glassdoor site?
2 weeks UI design – 1 engineer,
1 month development – 20 engineers,
1 month testing – 10 engineers.
development: $124,135/12 * 20 = about 207,000$
Google Senior Software Engineer average salary $124,135 (according to glassdoor)
management: $102,300/12 = about $8,000
Google Project Manager average salary $102,300 (according to glassdoor)
UI design: $85,706/12/2 = about $3,500
Google User Interface Designer average salary $85,706 (according to glassdoor)
testing: $103,125/12 * 10 = about $56,000
Software Engineer III average salary $103,125 (according to glassdoor)
overall: about 274,500$
Cheap marketing
Google can get some exclusive agreements with popular brands, local retailers in exchange of some price reductions on Adsense, and sell adsense ads on terms that close to Groupon.