Im not a expert but..
F1 cars do use a system based on puematic valves, however Im not sure exactly how it works, only that it allowed them to lift the rev limits from 12,000 to ~ 18,000 RPM.. But requires constant head rebuilds etc..
Lotus's new desiel Elise thing uses electric valve accuation as well as Direct injection Desiel things, which desiels really require because you don't have spark ignition to play with, but with total control over valves and injection you can do quite alot.
A VCT engine simple advances or retards the cam shaft(s) a few degrees sometimes by quite alot, userally hydraulically, but newer systems use electric system based on magnets such as the very new nissan engines in japan. This allows a fair amount of adjustment in DOHC systems in which you can control overlap etc. In fords SOHC case, it doesn't do much at all really, scince you can't adjust inlet and outlet seperately, a DOHC VCT falcon engine I would expect would make alot more than the SOHC.
The problem with total electronic valve accuation is its quite tricky to do on a high reving engine while still maintaining reliable function and cost effective. BMW etc are spending a fair bit reseaching this because the pay offs can be quite large in design flexability, driveability, emissions, power, powerband, torque, fuel economy etc. It will require a much beefed up alternator system, running higher than 12 volts to work, more than 24, more like 48 volts.
Really at this stage I think we can do alot with GDI and VCT DOHC engines and turbos. In the new skylines the 3.0 and 3.5 V6 put out quite alot of power and torque, naturally asperated. Turboed these things would provide better bottom end between 700-2000 RPM and then you with a decent VCT system work up on making a screaming top rev rush, with reduced pinging due to stratofying the fuel in the cylinder.. And do it cheaper than using electro valves.
The new GT-R should be a interesting engine with the Turbo V6's.. The naturally asperated 3.0 Neo DI puts out 191Kw and ~324nm of torque. A 3.5L of the same specs would make 223Kw and 378 Nm (more than the current RB26DETT in the GTR). Twin Turboed and you talking ~300Kw and ~500Nm easy, with great low down torque too (like more than a stroked windsor).
A 4.5 L Naturally asperated V8 which might go into export models would make 287 Kw and 486 Nm of torque. A 5L would make 320Kw/540Nm.. Turbo those and you will get seriously stupid figures and room for more.. Yet 5.0 L is hardly huge, and would be more economical than a 3.0 Camry.
But then again, instead on a V6 cylinder engine, 6xGDI injectors (expensive) + 24 valves and lifters etc + 2x DOHC, you just have 12 electric valves then it could make for interesting competition.
But what I really want to do use all the technology on one big fat engine.. 6 Litre V12, 48 electric valves, GDI, turbos etc..