The major features of RC4 will be Darksend+ and the lifting of the 10DRK send limit. A few smaller items will make it in, but things like IP Obfuscation will be after DS+ is fully implemented and working smoothly.
The rumor about RC4 dropping this week is just rumor. We'll make an announcement when we get closer.
You'll already get ip obfuscation pretty much, actually very well in RC4. So I see no big need other than for future services. I'm not saying we shouldn't do it, just that it's basically there, with the levels of masternodes, by the end, nobody can know where the coins came from, even if the first MN recorded IP, they won't know which change belonged to that IP.
But I can understand if someone didn't even want it known that their IP holds a wallet.
Sorry for the drive by, looks slow today, couldn't stop myself, LOL