Bleach is a world of it's own. Either you're in it, or you avert your eyes and don't be in it at all.
It's a visual experience. Both the illustration and composition style are very artistic and adds to the atmosphere. True to the shonen manga genre, it's filled with moments that makes you think "HOLY CRAP THAT IS SO COOL/AWESOME/BADASS/". The use of Japanese brush and ink in the manga not only adds to the texture, but also increases the atmosphere of the Shinigami world. The character design are colorful and interesting. There are plenty of characters that caters to all readers. Manly man? Check. Manly manly manly man? Check. Bouncy babes? Check. Cute innocent girls? Check. Tsundere? Check.
The story itself, for me, is amazing. For a manga in the shonen genre that cannot avoid plot devices and cliches, Bleach still manages to make you think that there's still a unique freshness to it. The 'damsel in distress' plus 'badass fighting chicks' trope gets used a lot, and 'unlikely savior at the last minute' cliche happens very often. The 'Oh you cut me! Oh wait no you didn't lol' thing was exciting for the first hundred times, but gets a bit repetitive. I don't really mind it that much since I can still find it exciting, but if you're the type of reader that goes "Oh, not THIS again" you'll probably be bored by the 21th volume (end of execution arc). That's around the time I stopped before I started again recently.
Rumor has it that the series is ending soon (although it's unlikely the way I saw it) and I think it's about time, although for me it's a bit sad. The heroes just keep getting stronger and stronger, and even though I keep thinking 'WHOA that is so badass", the enemies ALSO keeps getting stronger, and THEN the heroes unleashed an even GREATER power. Of course it wouldn't be interesting if the enemies are weaker, so whoa now the enemy is EVEN stronger. But wait! Let's train some more! Now the heroes are stronger. Repeat the cycle a couple of times and all of the sudden you have god vs. god. True story.
Also about you-know-who who didn't die, I think he will come back in the future and become an ally. It's just a guess, but if it came true I called it.
All in all I'm glad I read Bleach and would recommend it to anyone that loves that heroic ass kicking moments. I know I said there are lots of cliches, but even knowing that reading Bleach can still keep me on the edge so I think you can still enjoy it too.
I can't really say anything about the anime yet, but there are a lot of unrelated filler arcs that I would suggest you avoid. Start from the manga first.