I have not read all of the replies on this thread but there are some things about 8th ed which I think makes a big differense in the Lizardmen army. This is my first reply in this forum and english is not my native language so please have patience.
1. The Slann has truly become the master of Magic. He is great with almost any lore but with lore of Life the Army gets a buff that is out of this world. Be carefull to give your saurus T 8 when a screaming bell is on the table. Check what happens if it rolls 12-13.
2. The Saurus heroes have great new magic items to choose from so they can become really strong.
3. Taking spears with Saurus warriors takes more warriors to get the effect we had before. I prefer HW and shield. They survive longer at a lower cost and you dont have to have three ranks of them to be effective.
4. About COC. I dont know how to use heavy cavalary effective yet. I try but they die insanly fast in the magic and shooting phase and with steadfast they cannot charge from the front and there are never enough of them to break ranks if they get into the side. On top of that they are very expensive. Can someone explain how you use them effectivly?
5. TG die faster now that you have to use halberds and with I 2 they would have been better with Great Weapons. But there is not much you can do. They are still good.
6. Skrox are better since the enemy cant hit the krox in close combat. They have to plow through the skinks and that takes time so hopefully you break them before the krox gets it.
7. Terradons are even better. Now they are Fast Cav Skirmishers and have Stomp. Superb for warmachine hunting.
8. Sallys are one of the best shooting units in the game now. Move and fire and they hit many models and few are allowed armour save. Using them against high elves quickly get there points back. Extra tasty to burn swordmasters.

Razordon have nothing to put up against their fiery cousins.
9. Stegadons gained some abilities but thanks to steadfast they can no longer rush units and break them. I still find them effective if properly used. I dont use EoG anymore since the slann is about the same cost and way better.
10. Skink skirmish cant wall anymore so I use ranked skinks as rankbreakers. Very good to have saurus in the enemies front and skinks in the side. They get a 6+ ward save in close combat and if they dont charge they can still throw posion javelins.
These are the conclusions I made during my games with the lizzies since the summer. Please comment and tell me what you think about it.