new owner of a XV6800

[Lateadopter]

My XV6800 arrived yesterday. I was looking for a smart phone with wifi, but I didn't want to be locked into paying for a data package. Before I start changing anything on the phone I wanted to try and find out if I should continue using the wm 6.1 or is to possible to upgrade to 6.5? Also verizon is telling me that the sd expansion slot will only exept up to 4gb. Is this true, or can I use a 8gb or 16gb card?

I'm very excited to see what this phone can do, but I am a bit overwhelmed with all the differed suggestions on this forum dating back the last few years. What should I modify first, inorder to get the full potential out of this phone?