This came to me recently when both my husband & I noticed a change in the Budgies lads - when I'm away working for more than a day at a time.
The Budgies live in the back 1/2 of our apt. They have 3 rooms & a hallway to fly around. They have a Christmas cactus & hibiscus tree, many window shades, lamps, cages & a perch to hang out.
When we come home:
They have always called out to us.
They fly back & forth down the hallway so they can see us.
They follow us from room to room & will sometimes land on us.
Their chatter can be a lot louder & they have a lot to say.
They will display jealousy & competition [who gets to sit where] & often fly off in a burst of noise & energy.
They always greet the new person & often ask for attention - just a chat really.
When my husband or I'm away a lot: 
They fly onto us immediately.
They keep flying to one of us & sit on our shoulders & head.
Laker will sit beside me & stare - then walk up my arm & roost.
Rio will hang from my hair & peer down at me or sit on the window drape & shout at me - boy is he loud.
They tend to sit in front of my husband, on his desk.
Normally when we are home:
They will come to the rooms we are working in - or reading in.
They will run over everything we have - books, work, keyboard.
They call out to us if we aren't in the back for long.
They hang out 75% with each other & fly, nap, eat & have singing competitions.
They check on us on a regular basis.
They expect interaction - both physical or verbal.

I think that's it ....What about you?