Yep. The confirmation time is exponentially distributed with mean parameter λ^-1 = 10 minutes. This means the expected waiting time for the next block to be mined, is always 10 minutes from now, regardless of when 'now' is (even if 'now' is already 9½ minutes after the last block was mined).

The actual calculation is here but this is just a common property of exponential probabilities, as is the case with a random continuous time process like Bitcoin mining.

The non-intuitive part probably comes from this: at frist, you may think that with an average block time of 10 minutes, and transactions being randomly broadcasted anywhere between the current (last known) block and the next, the average confirmation time would be 5 minutes. But this were only true if block times were uniformly distributed with a mean of 10 minutes. They're not. Some blocks may take only 2 or 3 minutes to be found, others may take more than 30. Both are exceptional, however with random transactions being continuously broadcasted, obviously there will be more in a 30 minute gap than in a 2 minute gap. It all evens out nicely.