Halo 3 killed the franchise for me. I think Reach just redeemed it. Everything I loved about CE and 2 are back!!!
In reality, I wasn't quite sick of the gameplay, just unsatisified.
Halo 3 had a lot of awful points. For one, the 6 hour campaign that hardly made any sense. I went from thinking I was "Finishing the Fight" too "Why the **** am I in the middle of nowhere (the ark) and not on earth kicking some elite ass?" I found myself thinking that the Brutes are awful enemies. They're no where near as interesting or as fun to fight as the agile Elite was back in CE and Halo 2. They're sluggish and stupid. The story of 3 felt extremely cheap to me as well. No real big revelations were found (we barely found out who the forerunners truly were) and too make matters worse they switched up voice actors on many of the main characters. Not to mention the Flood Overmind (can't remember his name right off the bat) didn't even make an appearance! Don't even get me started on the awful equipment, awful new vehicles, awful maps (Epitaph ****ing sucks. so does Snowblind) and awful new weapons. Lets just say Halo 3 left a really really bad taste in my mouth. If you didn't like 3 don't give up on Halo however. REACH is the game any REAL Halo fan has been waiting for.
The Campaign is a tad longer then 3 was but the real praises can be seen in it's story. Reach had a strong source material in the novel and it shows in the game. The characters are easily likable and the voice acting is rather well done. The game plays like a dream. It's a weird hybrid of Halo CE (gameplay) and Halo 3 (graphics) that I'm really enjoying. You start off with the Assault rifle and Pistol (btw the pistol is back!) and it's all very reminiscent of Halo CE's first couple of missions. Dual wielding is gone (good riddance) and health is back as well, (Though shields are really what matters here). Marty O'donnel returns for one last Halo OST and finally he's introducing some new material (unlike in 3 where it was all rehashed Halo 1/2 Music) it's a very moody and foreboding OST and quite possibly some of Marty's best work.
The Multiplayer is of course where it's at and finally Bungie got matchmaking right. Getting into a game is a lot faster then it was in both 2 and 3. It's not as fast as Call of Duty MW2 but it's a hell of a lot faster then it used to be. The ranking system is very similiar to MW2's in that you'll earn experience and points which you spend on new armor and other in game bonuses such as Voice Over's for your Spartan. Customization options in this game are completely staggering. You could spend an entire year with the system just tinkering and messing with things. Forge is back as well as theater which is a good thing. If Halo 3 did anything right it was the Forge and Theater modes. Honestly, I can't believe I had to wait 6 years for a true Halo game to come out. REACH has redeemed the series for me. It's a much more interesting and polished experience this time around and it's honestly sad to see Bungie leave the series after all these years. At least they left us with their best work yet.
To put it simply, If you thought you were tired of Halo and had moved on too bigger and better things (MW2, Team Fortress 2, Gears) you definitely need to think again.
REACH is not to be missed.