RC = "Release Candidate", it means that the beta patch is nearly completed and almost good enough to be an official "final patch". it is a "candidate" (eg eligable) for release (soon)
it usually means that most elements they are working on are near finished, and they are confident it is almost ready to be given official status. it is released in this "condition" as a final check to look for some final residual issues and bugs they might not have had extensive enough testing for "in house", so they release it to the public for feedback. big companies with large software programs can go through a series of Release Candidate patches (eg RC1, RC2, RC3 etc..) that they release to their beta testers as they get closer to releasing the final product (microsoft usually does this with their main programs). other smaller software houses might just have a RC1 and maybe RC2, and then produce the final patch/program
looking at the amount of residual problems and some new bugs in the latest beta patch, i'd say they are nowhere near having a final patch ready, and will need a big push focused on dealing with all the major bugs/errors and add some missing features, quiet a big job
since luthier indicated his programers might now be able to focus on resolving CoD issues and take a pause from working on BoM, hopefully we will still get that effort
