Bought the game the first day and got a promo cd.

Sounds like the 3rd track is played by a string quartet, (2 violins, bass, cello), accordion (of course) and piano, even though the artists are called the "Layton Grand Caravan Orchestra".
It's the same music as heard in the LTT trailer.

I like the music series a lot, more than the game itself.
First Game was pretty good but tough.

http://www.sendspace.com/file/pfyxnr

The official osts come out next month or so.

Gotta agree with that.  The game irritated me to no end.  I definitely won't be buying the other two if and when they come to the U.S.  I will be buying the OSTs, though.

Also, an anime film has been announced: http://kotaku.com/5099532/professor-lay … ature-film

Wow, thanks for posting, that sampler is SWEET.

Not sure whether the awesome music is more the result of the composer (Tomohito Nishiura) or the arranger (Norihito Sumitomo) but together it's a damn fine combination!

Now I'm seriously contemplating having to pick up the 3 Layton OSTs which are coming out around the corner. (PKCF-1007, 1008, 1009)

I'm going to be getting the three Layton soundtracks as well when they release. Really looking forward to it.

Sumitomo only arranged the orchestrated track (the 3rd, but I'm sure you've noticed...).

But the first two soundtracks will have 4 orchestrated tracks each (arranged by Sumitomo and performed by Layton Grand Caravan Orchestra with Tetsuya Kuwayama), so I'm really looking forward to it, because if they are as awesome as the main theme for The Last Time Travel, we'll probably have some of the best music by Nishiura to date.

Yes, his compositions here are much improved over the earlier Dark Cloud and Dark Chronicle works, but just close enough to recognize his composing style. 
I agree it's sounding like his best work so far, so his talents seem to be growing.