Been playing it a bit and it's definitely an upgrade. I didn't *really* like the first one, but this one has some serious shades of brilliance. There are still some weird quirks (I have to watch ALL of my allies every move??!) but the game looks much prettier, the UI is much improved, the new races are fun and the new campaign is really great. It's not as deep as say, Civ 5 with expansions, but it is much deeper than it was before and a LOT more fun.
I really like Paradox, so supporting them here is a no brainer for me. If you have $30 to spend here, it's well worth it in my humble opinion.