Yes, your update is correct. Only the v10 Digital Download version currently offered at X-Plane.com will come with a free copy of X-Plane 11.
Please understand you do NOT need to purchase v10 again.
Just like in the past, there is no "upgrade" from V10 to V11. You can buy the special Combo Package that we are offering now - a Digital License and Serial Number to X-Plane 10 that will also unlock X-Plane 11 (for free) or you can buy V11 outright when it is released. In either case, the price will be the same, $60.00. You can order the combo package currently at x-plane.com.