In the Old Testament, God gave blessings that were for the most part physical in nature:  long life, wealth, land, children, and so forth.  In the New Testament we see a shift in the nature of blessings to something more spiritually oriented.  This verse (see above) clearly says for us that God is giving spiritual blessings today (I am not saying that God no longer gives physical blessings, simply that God's primary mode of blessing has become spiritual.) 

Actually the verse says far more than that.  It says that God has (past tense) given us in Christ (believers) every spiritual blessing!!!  Remember the hymn about showers of blessings?  Well this verse says that God dumped out the whole bucket on us!

I wonder though, why spiritual blessings instead of physical?  Here are some possibilities.
1.  Physical Blessings are temporary, Spiritual ones are eternal--Jesus himself says that treasure on Earth is subject to thievery and decay.  (Matt. 6:19-21)
2.  Satan can corrupt physical blessings--Job found this out and suffered greatly in the process.
3.  True Life is found in the insubstantial--Love, Joy, Peace, Patience, Kindness, Goodness, Faithfulness, Gentleness, Self-Control, Faith, Hope, Wisdom, Contentment, Righteousness,-----relationships, emotions, values, ideas, etc.

The verse goes on to say that the whole bucketful of spiritual blessings which has been given to us has been given to us "in the heavenly places."  In other words the blessings are ours, but we don't have full access to them yet.  Sort of like a trust fund.  Later in this chapter we see that we are given a deposit/down payment of the blessings now (Eph 1:14).

Why the heavenly places and not here and now?  Here are some possibilities-Just thinking here not saying any of these are true or "right".
1.  There for us to grow into--Like a trust fund is released when a person reaches an age where they will be able to handle it responsibly, God releases our blessings to us when we are mature enough to handle them.
2.  So we can relate to unbelievers--if we had the full measure of the blessings of God now, would we be so otherwordly as to be unable to relate and witness to those who don't know Christ?
3.  To allow time--Could the giving of ALL the blessings mean necessarily the beginning of the age to come?  If so, then God is waiting until all the sheep are in the fold.

I don't know the answers to these questions, but I can sure agree with Paul when he says, Blessed be the God and Father of our Lord Jesus Christ who gives us these blessings!!!! 
Here's all the Blessings in my poor power to pour out back to you Father God!  May your name be forever Praised!