IMO its not currently worth it. They are supposedly planning on increasing the benefits of a gold/LT sub, but have not discussed any specifics or given any kind of ETA on when this will happen.
I am always suspicious of these "marketing maneuvers" by some companies. Maybe they have already some stuff on the bag ready for life timers or subscribers to get more money, maybe that is why they are trying to get more people to pay for it.
If by the time they release the "benefits" of a subscription or a Life time one, I bet the price will skyrocket.
The only advantage of a LTS is if you plan to subscribe for a long time, so that it becomes a cost benefit. I held my LTS long enough before F2P so that it was cheaper than subscribing long term. The question should really be "Is subscribing worth it".
Back in the day, I threw about $350 in total at WoW. I dropped it because of other MMOs that were less expensive and have greater detail and better plots. I am silver (F2P) but I had questioned that advert myself, I could still end up tossing lots of money at Perfect World for even more Zen. Currently I think I spent about $10 here but I have been looking at the costumes and such. If WoW had offered LTS I may still be there... nah.