Another great reason to not use oak wine barrels:

Read this scary article!  Opus One sues a maker of wine barrels, alleging cork taint (TCA) in the barrels. Wow.

There are many reasons not to age wine in wooden barrels: They leak. They are expensive. They have a limited useful life. They are more work to maintain. Stacking them in barrel racks uses up more winery space than ceretain other forms of storage. And they can be infected.

There is a better alternative: Simply put the oak into the wine! Oak chips, oak cubes, oak staves. Easy.