Well I have a PS3 and at the time I got it there were loads of special offers for blu-ray movies (5 free with my PS3 and tons of website that were 2-for-1 offers or better) so needless to say I have a decent collection of about 30 blu-ray movies that cost me less than if I were to buy them on DVD. That aside, personally I feel the difference between DVD and blu-ray is as drastic and awesome as the difference between VHS and DVD was, so nearly every movie I watch on blu-ray, imo, is awesome and worth it.
But for some good recommendations, well it depends on the types of movies you enjoy watching, but a few that I enjoyed were;
- The Fifth Element (I was really impressed an old movie from the 90s could look so good)
- Lord of War (nothing like having a crystal clear picture & audio to help you get into the story and emotion of a movie)
- Ultra Violet (ya, its a kinda cheesy comic book movie, but the visual effects and styling of this movie are stunning, the only thing better than blu-ray on this would be the imax)
- House of Flying Daggers (yes, its subtitled but the uncompressed audio is amazing and coupled with the visuals in this movie really help tell a great story)
- Corpse Bride (wow, just wow. The wow factor for me on this movie was how clear the picture was, sometimes it was legitamely difficult to decern some of the textures from real cloth. To be fair though, I think in some places they actually did this, so I might be wrong, but either way this movie looks amazing.)
- Crank (I personally love this movie, a lot of people I've talked to don't like it for one reason or another, but I first watched it on DVD and then later on blu-ray and it nearly seems like a different movie. This movie benefits immensely from having great picture quality and audio)
- Planet Earth (this is a documentary basically about the ecosystem of our planet, its not too exciting but it is interesting to say the least. The important factor for this movie is it is absolutely beautiful, worth watching)
I personnally prefer blu-ray over DVD and I feel it offers a great amount of value for me when watching movies, as it stands the only experience that succeeds it would be an IMAX theatre. But to be fair blu-ray wouldn't be worth it if it isn't coupled with a nice 1080p HDTV and a decent sound system so it is a substancial investment for someone that is looking to just watch movies. Blu-ray is more of a side benefit for me because my home theatre is mostly used to play video games.
As far as I'm concerned blu-ray is still an early adopter's brand, based even on the comments in this thread its not ready for the mainstream, but I'm fairly confident it will come and I think a lot of the people here will enjoy watching their blu-ray movies in the future.