I think that after the crash in the -8 you now need 1500 hours to get a job in a regional US airline by law. Even if you don't he would not have a chance with 650 hours and a hand full of twin time. The US is not like Europe where you can get an airline job with 250 hours if you pay for a rating and are very lucky. In the US you need to work your way up the ladder and instructing is a good way to do it.
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Not correct. The 1500hr rule kicks in in August 2012. The regionals in the US are hiring like mad and my friends tell me that they can't even fill the hiring classes. Hiring minimums are anywhere from 1000hrs for the likes of Skywest to 600hrs for other regionals. They are trying to get their hiring done before the 1500hr rule kicks in, the change in rest rules which will require additional crews, and the anticipated retirements at the majors which will lead to pilots jumping from the regionals to the majors.
By the way, in 2008, some of the regionals did have 250hr hiring minimums in the US.