Before stating that specific titles sold more than others, please provide a source.
Reckoning sold 330,000 copies in its first month of sales (according to numerous sources). Not bad for an original IP.
Devil Survivor 2 sold aproximately .07 million copies in the US and .19 worldwide (according to the only source I could find - VGchartz, which I'm not a fan of). That's far less than Reckoning's 330,000.
I couldn't find anything on the US sales of Tales of Graces f except that it's original release did very well - in Japan.
As for Final Fantasy 13-2, a series that has been around for 25 years is expected to do better than one that has been around for 0 years. Still, the title did 350,000 in its first month - only marginally better than Amalur. Of course the Japanese sales are respectable (though low for the series average - doing less than FFXIII).
Now if we pick a more proven western commodity, which would be fair, like Skyrim the figures are quite different.
Skyrim sold over 3.4 million copies in its first two days. That's a big difference.