Yes, but Shepard could have been involved. Not set in stone either way. That's what I"m saying. So saying something is canon, as far as I understand, means basically nothing. Other than the major events, like the SR1 getting blown up. But when the player has a choice, there is no set canon. That's why I'm having trouble with people saying one thing is canon when the other option has an equal chance at being canon, as well.
I see canon as something that is true for all players, regardless of their choices. Arrival relay blowing up is such thing, Liara becoming new Shadow Broker, Shepard using Prothean beacon (which should've been not canon but Liara explicitly mentions it multiple times even in a non-import playthrough) - all are fixed and true for all players.
Player's choice is not canon as in Shepard saving Amanda Kenson, Shepard helping Liara to take down the Shadow Broker, Shepard sacrificing the Council.
Those choices are addressed in further games as in "there is not much information on what happened". See Oblivion Crysis for an example of how Bethesda dealt with player choice in their next installment.
Edit: If you talk about Shepard helping those mercs Liara hires or that Alliance squad Hackett sends - there is no information supporting that in the game and it ventures in the area of headcanon