"they will buy a lot of talent."
Not necessarily. They will certainly pay for a lot of talent: whether it's still there in six months' time is another question entirely.
If IBM's corporate culture manages to drive away a sufficient number of good RH staff (who, arguably, are pound-for-pound a more valuable resource than the average IBM equivalent) then the money will have been a spectacular waste. After all, if they'd merely wanted an OS, they could be using CentOS :-) and my guess is IBM will have to work hard to overcome RH customers' natural (and IMHO largely justified) suspicion of Big Blue.
What happens over the next 12—24 months will be ... interesting. Usually the acquisition of a relatively young, limber outfit with modern product and service by one of the slow-witted traditional brontosaurs does not end well.