Giving this its own post rather than letting it languish in a Facebook comment thread, a Seussish response to ‘is tomorrow 100% Saturday?’:
It’s hard to be totally sure of the day,
When time zones are stretching out every which way.
When you fly westward, whose hours do you borrow?
And when you fly east, do you get there tomorrow?
Sometimes it’s safer to go south or north
If you do need to gallivant backwards and forth
But everyone’s place has its own kind of time
(Which makes this an awfully challenging rhyme.)
It’s nine in the morning in Honolulu,
But ten hours later around Timbuktu,
At least that’s what I think – it might be eleven,
Or possibly eight and three quarters point seven.
But wherever you are and whoever you be
In Ottawa, Canberra or Tripoli,
It only can ever be one day at once
Midnight can’t change in these temporal stunts.
In another three hours and one little bit,
Friday gets up so Saturday can sit,
In Eastern Time, anyway, others may vary,
But Saturday’s Saturday, never contrary.
That hundred percentness is perfectly right
For one entire day and two parts of a night….
(But if you have lingered to read all these ravings,
Don’t get me started about Daylight Savings!)
That Other Blog, Way Over There 
And the requested elaboration:
Some things are needlessly overcomplex
Like colleges, mortgages, restaurants and sex,
But perhaps most of all in the pointlessness stakes
Is the lack of sense that Daylight Savings Time makes.
They say it was Franklin, that jolly old Ben,
Who always was one of the cleverest men,
Came up with the notion that twice in each year
We’d would have to go mess with the clockmaker’s gear
So all the clocks move an hour forward in springs
And later each year it’s the darnedest of things:
We move them right back to where they were before
Which raises the question of what it’s all for.
“It’s good for the farmers,” some people may say,
But I think that argument’s just making hay
The daytime is light in the sky just as long
Even with all the clocks set an hour wrong.
But don’t just ignore it until it’s thrown out
If everyone’s with it then don’t be without
‘Cause your boss might kick up one heck of a stink
If your clock and his get too far out of synch.
So right now our time system’s all out of whack,
But always spring forward and always fall back
And remember how Old Franklin pranked us and then
He sailed off to France, where he did it again.