User blog comment:N7EagleEye/New Mass Effect 4 Details/@comment-5607780-20121024230024

“So first, we don’t want to make ‘Shepard 2′, or Mass Effect 4 with like, ‘oh there’s no more Shepard but you’re a soldier in the universe’. So this will be a very, very different context for sure, and nothing has been decided on the rest.”

This doesn't necessarily mean you wont be a soldier. But even if it did, as many other people commenting have pointed out, that doesn't necessarily mean you wont be shooting at stuff. According to the Oxford English Dictionary soldier is:

" noun   1) a person who serves in an army.    (also common soldier or private soldier) a private in an army.

2) Entomology a wingless caste of ant or termite with a large specially modified head and jaws, involved chiefly in defence.

3)British informal a strip of bread or toast, used for dipping into a soft-boiled egg.

4) [usually as modifier] an upright brick, timber, or other building element."

An army is defined as:

noun (plural armies)

1) [treated as singular or plural] an organized military force equipped for fighting on land.

(the army) the part of a country’s military force trained to fight on land: he joined the army at 16

2) (an army of/armies of) a large number of people or things: an army of photographers".

And so technically, since I'm pretty Shepard doesn't specialise for land-based combat he isn't a soldier. However, I'll grant you the assumption that the definition has changed slightly in 200 years. In which case, I'm pretty sure to be a soldier, one would still have to be a member of an organised military force, and I don't think Ceberus qualifies and such, hence Shepard wasn't a soldier in ME2.

Many of the squad member also were not soldiers per se, including:

-EDI -Garrus. -Jack. -Jacob. -Liara. -Miranda. -Mordin. -Samara. -Tali. -Thane. -Wrex.