I don't know what exactly will be sent, but it says on kickstarter that you'll get extra parts. so maybe there will be some different things to try out. Otherwise, it won't take much to make or find your own parts to hack into it.
It's hard to say it will be more hackable than the production ones, just that it is a lot earlier in development than a typical beta. If it was a typical beta it would be sent only a couple months before the production ones.