F1, B1 & B2 are not eligible
> But after that, you can apply for another visa (e.g. F1, B1, B2 or other) and maintain your status.
F1 are not eligible, because they dont pay taxes. B1 and B2 are not allowed to work so the net effect is that you cannot claim unemployment benefits under other visa status. Heard on one radio discussion that immigrants who become citizen should not get benefits for 5 years after they are naturalised. There are lot of cases of abuse of the system hence those immigrants who work hard have reached a sad and difficult point. There could be more difficult times ahead.