I applied for a change of status from H1B to F1 this year. The application was received by USCIS on May 18th 2010. No decision has been made uptill now (today is December 21st 2010). My latest information has been from a month ago when I was told that my application needs a security check and that is what is happening right now.
My question is whether there is anything I can do to speed this up as such a long delay is affecting my career severely. I would really appreciate it if you could let me know of any channels that would allow me to expedite the process.

I applied for this change personally (i.e without a lawyer). Would hiring a lawyer now help in any way?

Thanks