I've got a little something to add to this point as well.
I noticed today while flipping around in v1.06.191 x64 that some of the specs for my drives were inaccurate or missing entirely.
Speccy reports that my two Seagate ST3500320AS drives (500GB, 7200) have 8MB cache, when in reality they both have 32MB. Interface also says "Unknown Interface" when it should say SATA2 (or SATAII, or SATA 3Gbps, take your pick since they're all the same). The temperature is fine though (corroborated by HD Tune Pro 4.50).
My third drive, a Western Digital WD2500JS-75NCB3 (250GB, 7200) is being reported as "TB/2.5-inch" under Form Factor, which is incorrect as it's a 3.5-inch drive. Interface says "Unknown" (missing the "Interface" part as the above drives show). The temperature for this one is also correct, again corroborated by the same application as above.
Personally, I think the SMART data presentation could be a little more user-friendly. HD Tune provides both the raw data as Speccy does, but also gives you translations in layman's terms along with converting the raw data into units that you can make sense of when you select individual SMART entries.
The interface type issue absolutely needs to be addressed though. I can see where this would cause problems/delays as pointed out above for people using it as a means to audit machines in the wild.