Are there any risks of getting a work permit under Obama plan?

There is always a risk when you have done something unlawful.  Considering that this plan recognizes that the action of your entering the United States illegally or staying beyond your lawful status was illegal and still grants a benefit means that as long as you meet all the eligibility requirements laid out by Janet Napolitano, you can be assured that no harm will come to you.  Here are a few other things to consider:
  1. You must meet all the requirements completely and clearly.  You must provide all the documentation and be able to prove their authenticity.  In your interaction with the USCIS, as long as you are completely honest and truthful, everything will go smoothly.
  2. If you do not meet some of the requirements -- for example, you have not completed your high school -- expect no harm other than wasted time and money because your application will simply be rejected.  That is why it is very important to make sure that you meet all eligibility requirements for Obama DREAM Act.  I doubt if you will see any more action than that because in another decision President Obama ordered that only undocumented immigrants who have committed grave crimes will be deported, but again, this policy has not been implemented perfectly, and you may still be subject to prosecution/deportation.  Again, it is best to consult with an attorney if you have doubts about your eligibility.
  3. If you do not meet a requirement related to your criminal history or if you can be considered as a threat to national security, things can get very nasty.  Since you have now provided all the information about you, chances are that law enforcement will act swiftly and mercilessly.  Expect immediate arrest and even deportation.  That is why if you have a criminal record, you must consult with a good attorney before applying for deferred action.  Do not forget that each case is subject to prosecutorial discretion so individual officers will review each case on its merits using the guidelines provided in the Department of Homeland Security memo and can recommend whatever action that they think is best.  There is NO APPEAL.