No, it isn't as addictive as evercrack.
Usually when people get addicted in MMOs they just keep playing.
It's like a nonstop cycle of better items and levels, the game is just set-uped that way.
SSBB isn't. And even if people do get addicted in SSBB, they usually start playing competitively, and once addicted SSBB players start losing, they start hating the game. Unlike when you're just playing casually, win or lose, you're just having fun.

Anyway, what I noticed from the threads that popped up when SSBB first came out, the general consensus around VGC gave me an impression that Subspace emissary is boring.
I think it's kind of fun playing with a friend.
And going by your impressions, it looks like I'm in for quite a treat.
Though I'm confident SSE still can't beat the fun experience of 4 player multiplayer, offline or online.
I would recommend paying offline multiplayer with some friends first , to get a feel for what it's like to play SSBB against other people, don't forget to turn items on. ^_^
Personally I prefer playing offline multiplayer better than online.

Anyways, keep in mind, my positive impressions are probably due, if part, to the great "fan service", which I loved. It was so funny watching Pikachu and Zero-Suit Samus running together. I love platformers so that's great. Some stages were tough if you picked the wrong crew but incredibly easy if you pick the right crew. The platforming wasn't hard but it was usually tight and imaginative.

I think what I would compare SSBB:SSE to is a Mario game like NSMB but with tons more options and replayability and a crapload of other stuff. It was just a lot of fun for me. Not that hard (cuz I played on easy) but each new level and the environments that looked like stuff from past games was perfect. And it played similar; it's like when Samus is running into a small room and there's one door and something to collect on the far side of the room, but it's a small room. Instantly I knew that a bunch of enemies were going to pop out either when I crossed the middle of the room or when I collected the object. And that's exactly how that level played! Woohooo, I love it! Maybe I'm just retarded. And I'm positive I'll be breaking this game out for years when my friends come over (well, my friend, I do really have one) and family visits a lot too (cousins, siblings, all their brood) and the Wii is just automatically turned on when they arrive. Well that's a different thread.

Not as addictive as evercrack or that fangled gizmo, WoW. That's good. I believe I've heard positive "stuff" from Melee players except they would argue over wave-dancing and items. But I do remember the update I think in December where Sakurai (one of my favorite producers now) said something like "real players use items".

Anyways, keep in mind, my positive impressions are probably due, if part, to the great "fan service", which I loved. It was so funny watching Pikachu and Zero-Suit Samus running together. I love platformers so that's great. Some stages were tough if you picked the wrong crew but incredibly easy if you pick the right crew. The platforming wasn't hard but it was usually tight and imaginative.

I think what I would compare SSBB:SSE to is a Mario game like NSMB but with tons more options and replayability and a crapload of other stuff. It was just a lot of fun for me. Not that hard (cuz I played on easy) but each new level and the environments that looked like stuff from past games was perfect. And it played similar; it's like when Samus is running into a small room and there's one door and something to collect on the far side of the room, but it's a small room. Instantly I knew that a bunch of enemies were going to pop out either when I crossed the middle of the room or when I collected the object. And that's exactly how that level played! Woohooo, I love it! Maybe I'm just retarded. And I'm positive I'll be breaking this game out for years when my friends come over (well, my friend, I do really have one) and family visits a lot too (cousins, siblings, all their brood) and the Wii is just automatically turned on when they arrive. Well that's a different thread.

Haha, the censored parts are so tempting. T_T
And yeah, I can relate with what you are talking about, about how they similarly remade stuff from the past games.
I was a very big Dk country fan back when I was a kid.
One of my favorites along with Super Mario World.
I remember those barrel shooting stages and the mario map 1-1 and 1-2.
Really nostalgic, moreso because of the remixed songs.
I could listen to Bramble blast all day. ^_^