what does this mean? "Your application is in the processing queu

Hi all,
My I-485 was filed in 05/2006. I received three udpate letters from NSC so far.

On 04/03, I received a letter saying “your case is current under review”.

On 05/31, I received a letter saying the following words:
The processing of your case has been delayed. A check of our records establishes that your case is not yet ready for decision, as the required investigation into your background check remains open.

on 07/11, I received a letter from NSC. It said:
++
Service records indicate your application is currently located at the NSC. Since the Department of State has recently made Visas current with many Employment Based applications, NSC is experiencing a much larger than normal inventory of cases that are awaiting processing. Your application is in the processing queue and will be processed as soon as possible. Please allow 60 days before you make any further inquires regarding the status of your case.

What does "Your application is in the processing queue and will be processed as soon as possible." mean?

It means:
1. your application recived visa and is waiting for immigration officer to process
or
2. nothing but a routine answer and my case is still waiting for name check clearence.

Thanks for any idea!
_(a)