I had tendinitis for a while after my ACL surgery. It's very common at the patellar tendon, where they harvest the material to craft a new ACL. The odd thing is that I thought most pro athletes got cadaver grafts so they can avoid this situation. The graft harvest site is always the worst part of the healing process, and with a cadaver graft you bypass all that.
In any case, it never got really bad - I didn't notice it while in the act of skiing, but the tendon would be screaming at me every lift ride up the mountain. It took about three years before it went away. Just in time for me to tear the other ACL!
Keep in mind I am not a freakish professional athlete with access to state of the art rehab facilities.