Well, there's pluses and minuses, but there's a reason that LEGO trains took off with traditional train fans during the 9V era - it's what made me switch, and I was very disappointed when they discontinued it. I was a LEGO novice, though, otherwise I'd have learned their track record for abandoning things people have invested so much money in.
The benefits of PF do not outweight the negatives, IMO, but it all depends on the individual and how they use their trains. Building a battery box into a train sucks. Replacing batteries in a built in battery box on a train sucks even worse. Rechargable helps, but then you have to stop and let the train recharge. The degree of control you get with the LEGO remote controls is terrible, too... it might be better if they did radio control instead of IR RC.
On the up side, there are definitely some benefits to PF. Lights stay on full and are not dependent on train speed; you can have discrete control of other onboard things - cranes, doors, whatever. There's also the fact that TLG no longer produces 9V compatible track.
HOWEVER, I say you can have the best of both worlds. In fact, when it comes to lighting, local battery operated is better, instead of wires running all around and between cars... there are always option; the 9v battery adapter mod
works great for things like lights. No more of a pain to deal with than other PF batteries, easier to conceal, no wires running between trains - and with the LED lights, lasts a REALLY long time. Essentially, 9v battery mod or full size battery box, you get the best of both worlds.
Lifelights works even better (but a bit more expensive).
ME and Big Ben are taking up the slack on 9V track, and I have little doubt there will be an engine solution at some point - until then, I have four and not permanent layout anyway, so it's more than enough for me at the moment.
I DO have a handful of PF motors and track, and I've modded some new trains - like the Toy Story train, to run on PF. The AAA battery box hides nicely in the closed car.
There is room for both, but I simply prefer 9V and will defer to 9V when possible. If ever I feel like really "playing," and went all out with a full permanent layout, I'd prefer digitrax over LEGO IR RC.
Edited by fred67, 24 November 2012 - 01:48 AM.