Warcraft 4 wouldn't be made before SC2 is finished. The team working on those games is busy with SC2.

Warcraft 4 would be amazing

Outside of pleasing the Esports people, whom already are at home with Starcraft 2, it would storywise be a mess.
The people whom before never played a Warcraft game, will demand that thier little snowflake be imported into the game. So you'll get "PwnyPwnyElfyGirl!" saving the Horde and after that the Alliance. As those two sides will be the only two in the game.

Where before Horde and Alliance where only words used (Like they should be as they are generic as heck), they now will guarantee all the hard work done in Warcraft 3 will be undone. So all of the diversifying of armies, from Night Elves, Undead, Orcs, Humans, Blood Elves, Forsaken... will simply be red vs blue. Where the two colours are replaced by the two generic words.

It's what PwnypwnyElfyGirl wants, and what the snowflake sue will get. Haven't you noticed yet how "Everybody is special!" in the storyline of Pandaria?

So No... as a huge fan of Warcraft 2, then playing Warcraft 1 and then 3... I can't say I look forward to 4. Not because Blizzard can't do it, but because their fans allow them to be as lazy as they can be. As long as they please the sues, the Micheal Bay 'Sploshun lovers and the Esport teens.

PS:Esport Teens are not to be confused with actual Gaming Athletes. The former are just 12 year olds that think they are awesome while the latter are actual 12 till 19 year olds who can make a living out of it. There is a huge difference. ;).

what fomo? everything gets reset each season and you start new characters unless you're playing on the regular servers and then you're already maxxed anway and just need to participate in the new season stuff.