Thank you for producing such an awesome piece of software. I have been doing my local development on a Vagrant box for about a year now and in that time I have been able to move from OS X to Linux almost seamlessly thanks to Vagrant.
The only problem I have with it is the slowness of the default shared folders mechanism. Guess I need to bite the bullet one of these days switch to NFS.
In the next version of Vagrant (1.4), synced folder implementations can actually be standalone plugins: https://twitter.com/mitchellh/status/405442194573516801
This will allow us to much more quickly add in more implementations of this mechanism, some of which may provide excellent performance at the expense of perhaps being more difficult to setup or slower to start up. But the importance is that the framework is now _there_.
I think we'll see this improve greatly. :)
The performance is acceptable most of the times, other than when I am running one of those PHP frameworks that includes a million files to process each request.
Maybe, I'll try something like leaving the files on the guest and mount it on the host using SSHFS. My write performance will take a hit when I am editing files, but, if I can get rid of the sluggishness it will be worth it.