Yes --50% has been indexed and 50% more has to be done. You can become a volunteer and commit to indexing just one state. One that is not your state of interest, but in doing so you can find a lot of interesting information.
For one, I really Really feel some of those census takers should not have been allowed near paper or pen. Some of this penmanship is a REAL challenge to the eyes. I am now working on Fulton Ga. Now I know some of my ancestors migrated to this city but there were more women in the family than men born. I am hoping I will stumble on some information that will give me an idea of who the girls married. For a long while I was finding only white residents to be indexed, but now I am looking at a record with 'NEGROE' residents.
There are checks and balances to doing this indexing and family search has them in place. If you have been looking at bad writing on census records, over the years of doing research, you can figure out what the names are. Believe me some of this writing is totally illegible, but the family search has checks and balances. You do what you can.
So come on and try it. You won't get a pass or fail grade like in school. No one will put your name out there that you did a bad job. Help is needed. Just try.