I remember the pre-release Brawl experience as almost a blur. The game made its grand debut in 2006, but wasn't released until 2008. While it was only about 2 years, it felt like I spent the latter half of my entire childhood waiting for the game. The game was announced when I was 12 or 13 - middle school was like a personal hell - and didn't release until I was just about 15. A lot can happen in those years, and I've always felt like my friends and I "grew up" around Brawl. When we first saw the trailer, we were ecstatic little children, but for months, there was absolutely no info, and at times, we were close to forgetting that the game was coming out at all. But the entire time, we were completely hyped. I'd talk Smash with everyone who wished to (and some who didn't), and we'd talk about our love for Melee, and which newcomers we most wanted to see. Snake was a constant buzz topic, and when Sonic was revealed, it revitalized the discussion and made everyone remember that Brawl was still coming, even despite the delay. "They delayed it? Even after all this time? And Sonic's in? This is no doubt going to be the most carefully-crafted, content-packed game ever. Brawl will be perfect." That was my exact thought.
Brawl's pre-release was so long and extended, and with that massive dry spell at the beginning, it just felt like years to me. I changed as a person several times in the interim between E3 2006 and March 2008. Went from middle school to high school. Made friends, lost friends. And during that entire time, even during the early dry period, I was entirely hyped. When the Dojo started its updates, things just exploded. Seeing pictures of everything in the game, from the characters, to the stages, to the most insignificant items, was mind-blowing. The graphics looked so good (to me) at the time, and compared to Melee, it was a significant jump. Almost every single newcomer was a fan favorite, so every time the Dojo updated with a new challenger, I was super-hyped. My friends and I would spend all day month talking about the latest newcomer, until the next one showed up. I actually kind of liked not having a trailer for each newcomer; the few pictures and move descriptions by Sakurai left a lot to the imagination, and I enjoyed that. Music updates were another particular favorite, and something I dearly miss this time around. Sonic's reveal, for me, can never be topped (Sonic was possibly my favorite game series at the time). Coming off of that hype was like crashing from a massive adrenaline rush that lasted for months. I had many similar reactions during that time (Pokémon Trainer as one example), but Smash 4 has only come close to the Sonic hype once, with Pac-Man (and it very well may have matched it).
Of course, when Brawl finally released, and I found out that it wasn't the type of game I was wanting or expecting (something close to Melee), it was pretty disappointing. But you know what? I didn't get any significant hype backlash. I really did enjoy most of what I was hyped about. Pre-Brawl was like a constant rollercoaster. Big updates, small updates, whatever. There was always at least something to talk about.
I find Smash 4's pre-release period to be a much more passive experience. We're just sort of sitting around and waiting for some juicy info. I think that the way Nintendo has been handling Smash 4's pre-release is overall more intelligent than how they managed Brawl's, as it helps prevent the hype backlash many experienced with that game, and doesn't spoil everything months in advance. I liked how open Sakurai was about Brawl, though. The daily blog posts were infinitely more insightful than the Pic of the Day, and by comparison to Smash 4, it felt more like an adventure that Sakurai was taking you on. Smash 4 has been much more esoteric, and I think the idea was to build hype while controlling it, but I honestly think that being more open with this type of info is a lot more fun. Business-wise, I think they're a bit smarter to save a good amount of info for when a big surprise is needed. Long story short: The Smash 4 pre-release era is smarter for Nintendo, but Brawl's was better for Nintendo (far more discussion and media hype), and was far more enjoyable for me.