I have graphics and sound on maximum (9).
Sometimes it slows then jumps in moving the camera (and that's probably my machine, considering it has Vista64, only 2GB RAM and onboard graphics/sound) but apart from that, I'm happy with my graphics.
The sound when hooked up to my two-speaker hi-fi is acceptable (I'm told a 5.1 setup is required to get the best out of the game).
All the acting sounds perfectly natural, except for Elaine's, which could be at least partly due to the sound compression.
I could tolerate re-use of character base models but in a professional game, it shouldn't really happen.
There were a few typos in the voice text in ep2 (most notably 'burry' and 'Esponga'), that I'd like to see fixed for the DVD.
Game controls are jittery. On my machine, the cursor doesn't have the same responsiveness as in the other MI games or the desktop. The character movement via mouse was probably conceived for the Wii and while I've got the hang of it, I appreciate most have reverted to centuries-old arrow keys and WASD. Due to inhibited cursor movement, combining items is real pain in the neck.
Hooking all the episodes together, perhaps with chapter-specific credits being in the menu, like in SMI: SE, would be nice (it is a MI game, after all).
Life is like an adventure game: if you don't click, you don't get it