Probably not what you meant, but meets the word of your question:
Altium's work area can be split into multiple windows (or windows dragged off into a new main window), so you can work on the schematic and PCB at the same time.
Object highlighting (select part on SCH, highlight footprint on PCB; but not the other way around) is nice, but properties aren't updated until you send the ECO ("update changes"). Also, the info panels swap activity in a somewhat ponderous manner when alternating focus between SCH and PCB, which slows things down.
There are probably desirable reasons to keep things neat and ECO'd -- like if corporate procedure requires change logs throughout the design process. And it's not at all uncommon for the SCH and PCB designers to be completely different people with little overlap, and only little back-annotation or changes requested; an instant sync (which could be enabled via network connectivity, give or take ping!) could be absolutely irritating.
I would imagine it not being terribly hard to keep things instantly in sync (perhaps a script could even implement this in most EDA systems?), but it may be more burden than help. Often you'll make considerable changes in the schematic, and they'll resolve themselves on the PCB without trouble; or, other times, you'll have broken links between SCH symbols and PCB footprints, and everything ends up discombobulated (a problem which could've been alleviated with incremental updates -- if you had remembered/considered to update the PCB as you went, maybe the carnage wouldn't have been so bad? But you were really concentrated on those changes!).
So I don't know offhand if there are any that are real-time synced, but there may be. A lot do it through some sort of ECO process, which ranges from horrible (e.g., obscure and irritating workflows like OrCAD + PADS) to relatively painless (as with Altium).
Tim