I'm guessing I'm about halfway through. I finished the third planet and stopped. Quick impressions..
30FPS is a real bummer. The animations aren't as impressive as a result. Ratchet feels weightless compared to previous games. Small things like smashing boxes for bolts isn't as satisfying. The combat isn't as gratifying. It also does drop when things get hectic. I had to stop playing because I got a headache.
That being said the game is still a lot of fun. Yevek was great, the jetpack battles are a blast. I hope they keep this for future installments. Graphics are great despite the drop in frame rate. I love the character design, the villains especially. Voice acting is great. I'm glad they brought Talwyn back, I always liked her in ToD, I think she should become part of the 'regular' cast.
Weapons are a bit hit and miss. I love bomb weapons, they're always my favorite, The fusion bomb (so far) is keeping up with that tradition. Probably my favorite so far. I really like the Winterizer even though I usually don't care for the morph weapons. Level 3 'Shotgun' is awesome, so is the Haunted Box thing, a good follow up to the Groovitron. The Netherblades suck. They were terrible in ACiT and they're just as bad now and they're a pain to upgrade. I'm hoping they turn into something fun. Mr Zurkon has worn out his welcome. I loved him back in ToD but it's boring now and a waste of a slot. The default pistols are okay. Nothing special (yet) but nothing terrible. Plasma Striker, same thing..it's okay. All of this can change depending on how they upgrade over the time though. I'm hoping for some good things from the not-so-good weapons.
Clank sections are good and most importantly they don't overstay their welcome.
Other little things I like. The map screen. The effect when Ratchet picks up bolts or health. The effect when Ratchet is walking on magnetic services.
Is there a reason why Al is called "Plumber", he's one of the few characters I remember from previous games. I'm surprised they reduced him into a no-name character.
Anyway. So far, so good. I see there's a challenge mode in there which is nice.