I'm assuming you're speaking of database integration. From what I understand, it is pretty easy to do. And it is naturally up to date since it uses the same information (from what I gather). So, basically (from what I understand), every time you update database info in one, it also applies to the other. It's something commonly referred to single sign on or consistent sign on.
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examples: http://tivocentral.co.nz/vanilla/ http://www.yeahnah.co.nz/vanilla/