Congrats OM! It's been a long road!
I would also echo the patience tactic if you care for your spouse. Saddly there is alot of bitterness towards JW's and many times I was advised to just divorce my wife because she was still active. Some see active witnesses as drones for a company that stole something from each of us. I prefer to see each active witness as a potential ex-witness.
It took me 8 years to free my wife and like OM mentioned, it happened when she was ready to look and after you peek behind the curtain, I don't think you can unlearn the sheer corruption and evil you see.
To add to OM's list I'll put what worked with my wife:
1) Try to act more neutral to counter the black/white thinking of the witnesses. Comment on things like how nice some homes look decorated for Christmas, mention good experiences you have with "worldly strangers". Comment on human relief efforts in lands undergoing crisis. It's hard to refute these points and it plants a seed that the organization isn't 100% right all the time.
2) Celebrate the holidays. Not openly or all out, but a bottle of wine on their birthday. Flowers or chocolate on Valentines, a small gift at Christmas, breakfast in bed on mothers/fathers day. These are just basic nice actions. If questioned about it being for the holiday, a sheepish smile and a "I just wanted to do something nice" worked for me. I would also do these same things year round so it falling on a holiday would trigger a twinge of guilty pleasure but that's another seed to create a longing to fit in for once rather than always apart from "the world"
3) Volunteer and encourage your partner to do the same. Let them meet people that genuinely care about others. Not to save their souls, or to fulfill prophesy so a vengeful god will destroy humanity, but because they want to. This is a quality that should be in a true religion, but largely lacking with the witnesses. The gossip, fighting and pettiness they see in the congregation can erode their faith and lower their desire to attend meetings.
4) Encourage reading books on religon or mind control. 1984 and Animal Farm are great. Even something like the DaVinci Code can open up critical thinking.
5) When she asked, I would go to meetings. But on the way home I would critique many of the points. Looking up outside publication "quotes" and finding the real context. Highlight times where the organization asks their members to do something that they don't do themselves.
6) Encourage them to seek out old contacts on social media such as MySpace or Facebook. Eventually this was the final nail that freed my wife. She had heard it from me and had already resolved in her mind that I was "weak" spiritually. When she started to reconnect with old friends from her youth that had left or were DF'd it provided a greater impact than I could ever have. All the seeds of doubt were there, but somebody else had to water them.
In all I think the most important thing is motive. Why do you want to free them? Is it a moral issue? Is it to get back at the organization? The big question I had to consider was "Am I willing to accept that my wife may never leave?" This mostly was a yes, though we did come to a head over raising the kids. I was willing to accept her going in service and meetings, but my deal breaker was that I didn't want the kids to be raised full witnesses. For me, knowing my regret and lost youth, I couldn't allow that to happen to my children.
Again, a big congrats to you and your wife OM! If she is interested in talking to my wife she would love it. I learned afterwards that there was alot of questions and emotions that went along with her leaving that she really didn't bring up to me. Feeling slightly betrayed over my double life, a bit tricked and questions of doubt and worry that I was just too elated to really notice.