Hi there i just have a couple of questions.

Recently i started a relationship with a long time friend Virgo.
born 25th August 1987

Could anyone give me some advice on Virgo & Cancer relationships?
What type of relationship can i expect!

he is very devoted to me and caring and fusses over me but he is also smart and likes to play on my weakness's at times.

i left this virgo waiting along time before i decided to start a relationship.

now what? will he be any diffrent form the perfect friend he is??

Is what you are going to get... Devoted, caring, knowing exactly what and how you like , well, anything.
Virgo's like to be 'mothered' and there isn't a more mothering sign than Cancer.  

 Devotion and loyalty is what you can expect from your Virgo beau.  Any other sign would have most likely split the scene long ago. But be advised, Virgo's love intellectual challanges and are known to argue or debate a point just for the sheer logical and critical exercise.  

Stah, you will also have to realize that just because your Sun Sign and His are 'highly compatible' , there are iother factors, such as the sign and houses of both his and your inner planets and how both of your charts interact that affect how you will be as a couple.

Case in point, I am a Virgo and my Wife is a Geminii.  Every reference that I have ever read or fellow astrologer I have ever consulted had told me that we won't work.  One Online compatability "calculator' scored us as a negative 2500.  BUT after having a proper synastry chart and reading done, I found that we had more than enough pulling for us to counteract our core personalities.  

  All of that aside, would you rather marry a stranger that you are "hopelessy head over heels in" and later, once the fog of romance has faded, find you cannot stand or your best friend?

Synastry and chart comparison is a complex business, so here is some research for you  

When looking at a woman’s chart the type of man she would look for is her sun sign and mars traits, plus 7th house planets and house cusp ruler and where that ruler was deposited.
When looking at a mans chart for the type of woman he would look for is his venus and moon sign and then 7th house planets and house cusp ruler and where that ruler was deposited.

Although synastry is a valuable tool with astrology it cannot 'make things happen' even if you have the best synastry in the world unfortunately..

If you want to research more into synastry try here
cafeastrology.com/astrology_of_relationships.html
cafeastrology.com/synastry/interchartaspects.html
cafeastrology.com/synastry_house_overlays.html
astrology-numerology.com/synastry.html
astrology-numerology.com/synastry-houses.html
astrology-numerology.com/synastryaspects.html
cosmitec-astrological-compatibility-advice.com/astrology-marriage.html
astrologyweekly.com/forum/showthread.php?t=17513
astrotheme.com/synastry_advice.php