A lot of games I either over-hyped and got bored of quickly (Most shooters) and didn't return often or came back later and really enjoyed (F:NV). A lot of great games I wasn't following before their release but I have loved since; Borderlands 2 (before it became grindy), The Walking Dead, and Far Car 3.
I know the danger I take in typing this, but the only game I ever put on a pedestal that never crumbled is probably Mass Effect 3. The ending was botched a little (though the EC healed that wound), but the closure of many character plot lines (Mordin, Legion, Grunt, Tali), and the -gasp- addition of Day 1 DLC character Javik brought engaging and emotional gameplay. No game is ever perfect even in it's best attributes (James, Ashley, Kaidan, and Miranda all needed to be fleshed out more), and it delivered an experience that has brought me back many times.
Before I post this, I almost forgot XCOM:EU, the other game that lived up to the hype. A friend pointed it out to me several months before release and convinced me to buy the original. Best advised I ever took.