As nobody seems to know the answer, and having been on the unreceiving end of a few unanswered threads I thought I'd give my two cents...
I don't know if the recipe or process has changed, although it's possible and probable, but I'd be inclined to blame your taste buds!
In my opinion and logically thinking, how a beer is perceived by your taste buds will change from hour-to-hour, day-to-day, month-to-month, etc. so I would more surprised if it tasted the same to be honest. Your mood, location, company and a million other factors can affect it too...
You can really only say how a beer tastes 'in the moment' so to speak, not how it will taste next time you have it. You could drink it next year and think, 'Meh...', again.
Anyway, those are my thoughts on it...
Liam