Here's where I am: 5 years to PFL. 900 XP banked, and about half of that in the past year. My nearest airport is a *A hub; I got hooked on FB when I was hub captive to them, and when I moved out here, the deal got better. I have a credit card I wouldn't otherwise use, and I put most of my big-ticket expenses on it. On the other hand, I've gotten more Y-to-J OpUps from *A with just a FF # than I've ever gotten as a FB Plat, and that's not mentioning the fact that those FB OpUps were intra-Europe and the *A ones were TATL. Okay, fine, I've also gotten 3 TATL AF/KL OpUps: 2 from Y to the glorious AF shell-seat W, and one from said shell W to J.
Anyway, I've not been banking these XP assuming FB would stay the same; I'm not an idiot. But I've got a lot of flying to do in the next few years. I'm currently both bringing premium revenue to AFKL and denying even more to their competition. This rumored XP cap would effectively offer my home team the chance to status match and give me a two-year trial period of non-stop flights, choice lounges, and optimal service. And, hell, if PFL is off the table, why would I even bother with FB?
We'll see what the future brings. I've given AFKL my loyalty; it's up to them to lose it.