That's what they've been saying forever. There have been studies and its been proven to have little to no effect.
Best thing to do is play the guitar and in time it will open up.
Also, this opening up doesn't apply to laminate top guitars.
Over at the "other" acoustic guitar discussion board:
We had an extensive discussion on this in the "general" thread. No firm conclusions. I tend to agree with John that a quality guitar made with good wood is going to sound good....
Wood will "settle in" to the ambient temperature and humidity conditions where it's kept (rather than where it was manufactured) and may sound a bit different after a while.... But most humans can't tell the difference.
Do we really, accurately remember exactly what our guitars sounded like when they were new?
AG magazine did an article on this very topic a few months ago. I am behind on my reading, though, so I do not remember which month it was. You may be able to do a search of some sort on their site to find it.
Lots of folks have tried this and I for one belive in the tooth fairy also as being real and truthful. No not really but it does bring a chuckle to me every time this comes up.
Wood needs to be played to open up and the wood needs to change over time as it would naturally, so no vibrations from a speaker will do no good to help open up your guitar.
There was a guitar maker who tried to blast their woods to see if they can get that to happen sooner then later but abandonded the program when they could not find any difference, but hey if you want to annoy your neighbours its up to you.ship