if you not include model or service on your project this found. :)
Buty if you add one model o one service on execute tns livesync android --emulator --watch this return an error.
I tried with typescript 2.0.3, 2.0.10, 2.1.4
and
npm -v
4.1.1
nodejs - v
6.9.4
ng -v
angular-cli:
1.0.0-beta.24
node: 6.9.4
os: linux x64
@angular/common: 2.3.1
@angular/compiler: 2.3.1
@angular/core: 2.3.1
@angular/forms: 2.3.1
@angular/http: 2.3.1
@angular/platform-browser: 2.3.1
@angular/platform-browser-dynamic: 2.3.1
@angular/router: 3.3.1
.. and i get this error:

increase the max amount of watches :
http://stackoverflow.com/questions/16748737/grunt-watch-error-waiting-fatal-error-watch-enospc
It's OK :) Thank you!
Most helpful comment
increase the max amount of watches :
http://stackoverflow.com/questions/16748737/grunt-watch-error-waiting-fatal-error-watch-enospc