Maybe it's me, but I don't see the downside to meeting him. It's not a good idea to alert someone before you throw a brick at them, but it doesn't sound to me like you are throwing a brick at them. You're addressing a different niche, and without knowing anything about what industry you're in, I'd bet dollars to doughnuts that the number of customers you are going to poach from each other is miniscule compared to the number of potential customers that are not buying from either of you.

In my last start-up, I had a good relationship with the CEO of my major competitor, even though I disrupted what was a very comfortable situation from him, and took a lot of business away from him-- and we were battling for the same, very small niche. I had a lot of respect for him, and entertained take-over proposals on several occasions.

So, my two cents: go for it. Be respectful and humble, share only as much as you are comfortable sharing, but be honest in what you do say.