Hello PendingN400,
Please see the memorandum and order for the Eng v. Chertoff attached.
The concurrent jurisdiction is OK (from our point of view) if USCIS actually makes progress and approves your petition, the problem is when they deny the application after the complaint based on 8 U.S.C. 1447(b) is filed with the district court. In that case the concurrent jurisdiction should be fought vigurously (mainly using the arguments from U.S. v. Hovsepian, 9th Cir. Court). Unfortunately, even if the court vacates the denial deciding that has exclusive jurisdiction, the judge still has the option to remand the matter to USCIS and as soon as they get back the jurisdiction, they can deny the application. I don't see a safe way how one can avoid such a situation... Any ideas?