Definitely boy! I much prefer
Jens though. I would love to see a little
Jens instead of Jensen.
Jens is pretty much the same but you actually use a proper first name and it's not nearly as trendy.
Some middle names to go with Jensen:
Jensen
MichaelJensen Rogue
Jensen Steel
Jensen
AloisJensen
ZacchaeusJensen
BraithJensen
KeirJensen Remington