yes, video recording is available with 4.5 OS.
as far as themes go, there are already a ton of bold themes made for the curve, just take some time to look around the forums.
As far as themes go, there's some that you can't even use unless you have 4.5, but yes there are plenty of themes out there that are similar to the Bold's. Some are exact replicas and some aren't so exact?
Just depends what your looking for.
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