I don't think Russia is merely "considering" air strikes as President Putin stated, that consideration was made a long time ago and a decision has already been reached.
Russia is just laying the ground work before executing that decision now.
And from the scope of those preparations, you can tell that the Russians really mean business. When their air strikes begin, it is going to be intensive and sustained, in contrast to the almost token pot shots the western air forces have largely taken thus far.
I think if the Russians wanted to, they could have started bombing operations days or even weeks ago. They are waiting on something.
That something could be Assad's ground forces to get organised for a big push to fully capitalise on the Russia tac air support, Iranian ground forces, or more significant players to make up their mind on whether of not to join the party...