They are not going to errata them. Those classes are still going to exist post-essentials and will still work. They aren't changing anything about the original ones and these are basically new builds.
That's not entirely true, see here: Dungeons & Dragons Roleplaying Game Official Home Page - Article (Commencing Countdown!)
At the very bottom you will see that, as part of Essentials, EVERY Wizard encounter power will be errata'd to have a miss effect. So classes from the original PHBs will be impacted by the changes introduced in Essentials. So other changes, including streamlining of primary ability scores, isn't totally outside the realm of possibility (except probably for warlocks, who would become immensely powerful if they could use all the different Pact powers with one primary attribute)
Last edited: