Today has an interesting way of sneaking up on us.   We always expect tomorrow, while commiserating about yesterday, yet Today always seems to be right there in the forefront. 
"Tomorrow I'll get it done,  or  "Look how good we did yesterday." is often overshadowed by "Today is the day".   Quite simply there is only Today anyway.  Today we were born, today we will live, and today we will die.  Your life is measured by what you do today.  So how is it that Today after Today we wake up and get it wrong?  We wake up believing that if we don't get it right today there is always tomorrow....Incorrect Sir.  There is no tomorrow.  This is only today.  365/366 days a year  All Today.  If you meet someone who says they woke up on tomorrow, buy that person a nice cool glass of "Get the Heck out of here"  (It should be noted that I wanted to say something more perverse here, but that's just not my M.O. , so this is as risqué as it's going to get.)  Alright down to brass tacks, if we strive to live our lives knowing we only have one day to operate in, we MAY be able to accomplish something worthwhile.   We MAY be able to leave a lasting and positive foot print on history and affect the lives of others in a positive way.   Those of us dreaming of tomorrow while regretting yesterday are not going to be able to take full advantage of the only Today they will get. 

Just a thought