seeeduino mega : 16 extra digital i/o

I was researching the Arduino Mega while searching for a microcontroller board on which I’d like to base a project, and came upon the Seeeduino Mega. Then I got all excited because of the extra digital ports without any futzing about with matrices or multiplexing. Then I saw this thread. Hopefully someone can answer some questions I have re: the Seeduino Mega’s extra digital ins and outs.

So, this is what I have gotten out of this discussion:

1: The Seeeduino Mega has 16 extra digi i/o pins, but these pins are difficult to use, and surely won’t be supported by the stantard Firmata sketch (which isn’t functional for the normal Arduino Mega, anyhow, according to info on the Arduino forum).

2: These extra 16 digi i/o’s cannot be used simultaneously with the 16 analog pins that they share traces/microcontroller pins with. Or can they?

3: The standard Arduino Mega may be able to do the same thing as the Seeeduino Mega and produce 16 more usable digital i/o’s; it would just require a firmware revision and some extra off-board wiring? Or is there more work which would have to be done to access these pins? …Or is this completely impossible on the original Mega? The way the posts above are worded, it seems the analog pins 0-15 share circuit board traces with the digital pins 54-69. which means that those digital pins are just duplicates, as you would get from stacked headers sprouting off of a shield on an Arduino. This theory would further confirm my suspicion that you can’t use the extra 16 digital pins at the same time as the analog pins.

So anyhow, could someone with experience confirm or deny any of this? I really want to purchase a Seeeduino to base a prototype of a production piece off of, but I can’t until I have this stuff figured out.

Cheers,
Scott