Pizzaslut, was going to ignore this thread (as I can't stand the competitive 'i'm busier than you' parenting rant) but just have to reply.
I have Dtwins (identical boys, 22 months) and a DD aged 4 and a half, she was 2 and 9 months when the twins were born. So I have experience of the toddler with newborn and twins!
Firstly, on a few occasions you've mentioned 'that twins have the same routine!' Don't make me laugh. Of course they're at the same stage developmentally, but they're not a two-headed beast, but rather two children who wake up at different times of the night (sometimes 4 times each on the same night) and have teething episodes a few days apart.
Other posters have mentioned the physicality of holding/winding/rocking twins as well as the managing of double buggy/high chairs in shops/restaurants.
And no one, no one, only other mothers of twins, can descibe what the first year was like - dealing with premature babies, constant conveyor belt of feeding/changing, having to leave one down crying while you winded the other (i used to think that you could at least pace the floor all night with one child but not twins) and the sleep deprivation. Particular when I had to get up with DD1 - after maybe 20 mins sleep a night (over months and monts as boys didn't sleep until 10 months).
However, the first year is the hardest. Currently, Dtwins are walking/running in different directions but you have to be more organised with twins about places you go and more limited, like I usually let all the 3 kids play in the backgarden, or if out in the park, it's back in the buggy after 15 mins and ply them with crackers!!
They say with twins, the big pay off is after about 3 and a half as they've someone to play with:) So yes, in some ways it gets a little easier.
My sister also has twin boys, and we amused ourselves with comments from some mothers who say 'I have 2 children very close together which is just like twins' 
Finally, just to say, I'm delighted with them, do it all with a smile on my face and am just delighted to have happy, healthy boys!!People in shops love to say 'oh poor you, you've your hands full, etc' whereas I just reply 'no actually, it's great'
Surely some people out there have it REALLY hard, children with a challenging disability, etc.??
I'm just not in to this moaning about all the work involved with parenting. I always think to myself 'someone wiped my bottom for me when I was a baby so roll up your sleeves and get on with it!! 