The photos aren't only there for looking at — collect enough of them and you'll unlock prizes within the game and those are things you will not want to miss, especially the first prize you unlock. I won't spoil it too much, but let's just say hearing what was said and seeing what was onscreen gave me the chills and left me with a smile that has lasted more than 24 hours. It is such an amazing addition to the title and a piece of musical history so uncommon these days that I almost long for the days without an internet so surprises like these are more commonplace.
As for the game engine, If you've played Rock Band 2 in any of its forms then this title will be familiar to you. Sure, the color palette has changed but it still feels like Rock Band. Even included is the Rock Band glitch where the fretboard or lyric scroll will seem to shudder or stammer when there's not much coming down the board.
The timing window doesn't seem to have changed either, but then again I wasn't playing guitar on the Expert level so I can't speak to the responsiveness of the HO/POs. But I will say that on drums, the game felt exactly like it should. Given the nature of the beats in the game though, there are some songs that are tougher to master than others but players who can hold their own on the Hard level on most Rock Band tracks will easily be able to take that on here, and even may venture up to expert for a good portion of the songs. Nothing to me seemed either under- or over-charted on drums which is a great thing. Two other bonuses for drummers in the game are a training mode with a slew of beats to master, as well as a section of 80+ other beats that are Beatles specific. These might be worth playing before diving too far into the story mode, as more exposure to the backbeat is a good thing.
Other nice features added to the game are the ability to view star ratings during quick play. I know this is something that is supposedly coming out in a patch to Rock Band 2, but it sure is nice to have here. Also, thankfully added is a countdown timer that appears after you unpause the game if you pause it mid-song. Who says competition isn't good for competing games, as this feature first appeared in Guitar Hero: World Tour.