The Forgotten Realms was my setting of choice in 2e, thanks to some really great setting books (like the 1e boxed set and Forgotten Realms Adventures)...ah, I miss setting books. I completely devoured the lore, and have been known to go to Candlekeep to figure out lore-friendly names for PC's, lol.
Eventually, though, the sheer weight of all the stuff going on in the novels, bolted-on sub-settings, and many, many supplements of dubious value (I mean, did we really need Warriors and Priests of the Realms?), let alone playing in other eras of history (I liked Netheril Empire of Magic and Cormanthyr Empire of Elves, but I totally admit it Arcane Age was a bizarre concept), I ditched the Realms, and didn't come back until 4e- ironic, since 4e made a mess of the Realms, but I was playing a lot of Living Forgotten Realms at the time.
Now? I really don't care for the setting at all, and only acquired the Sword Coast Adventurer's Guide because of it's player-facing content (even as, paradoxically, I often complain about no setting updates for the heartlands, Cormyr, or the Sea of Fallen Stars...).