James,

Typically the alignment arrow is a little different for each new Titleist Golf Ball release, I haven't bought my new Pro V1's yet, so I can't sat what the difference looks like, but that is the way you could tell with past releases.

Hope that helps. 

The side stamp is how you can tell visually.

                      2013                                                                  2015

I believe the alignment arrow is slightly different.  The 2013 model has the arrows as solid.  The "shaft" of the arrow is connected to the "head" of the arrow.  The 2015 model appears to have a break in arrow.  There is a slight separation between the "shaft" and the "head of the arrow.  At least this is how it appears through the photos on the website.

Ive heard but not seen that the alignment line has changed. 

Yes, the side "alignment" markings will be different on the 2015 model.  You should be able to tell right away, if you are familiar with the 2013-14 model.  I'm fired up to test the new V1x!!  But I think I'll hold out for the annual special order (buy 3 personalized dozen, get 1 free)

Hit em long and straight this year!

the arrows by the pro v logo are disconnected on the 2015 balls

Thank you for your question regarding Titleist golf balls. Below is a list of side-stamps that would designate the order-of-release starting with the original version:

PRO V1 392 ... 2000 - January 2001
< PRO V1 . 392 > ... February 2001 - January 2003
< . PRO V1 392 . > ... February 2003 - January 2005
< PRO V1 - 392 > ... February 2005 - January 2007
<----- Pro V1 -----> ... February 2007 - January 2009
< . ----- Pro V1 ----- . > ... February 2009 - February 2011
<---- Pro V1 ---->  ... February 2011 - February 2013
<---ProV1--->        ... February 2013 - January 2015
<  ---ProV1---  > ... January 2015 - present

We also released the Pro V1 Star and X which have the following side-stamps in the order-of-release:

< Pro V1 * 392 > ... February 2001 - January 2003
< . Pro V1x 332 . > ... February 2003 - January 2005
< Pro V1x - 332 > ... February 2005 - January 2007
<----- Pro V1x ------> February 2007 - January 2009
< . ----- Pro V1x ----- . > ... February 2009 - February 2011
<---- Pro V1x ---->  ... February 2011 - February 2013
<---ProV1x---> ... February 2013 - January 2015
<  ---ProV1x---  > ...January 2015 - present

I found a Pro V1x 332 on the course the other day that looked brand new.  Didn't realize they were that old.

Pretty impressive chart! Thanks!

I usually can't keep them long enough to know the difference. Thanks for the chart.  So is this a way to tell if the test sleeves are pro v's or v1x. I know they say test but is the arrow different.

Thanks, just what I was looking for. Titleist used to publish this info but i could not find it currently.

I prefer the 2015 on from the later ones but some time if I'm going to hit long I bring out my titles distance balls  but solo is good to!

arrows is a key to look for, also the out cover will feel different and the dimple sizes also.