Q:

Placing of copyright notice in source code

I'm about to release a project of mine that I'm really proud of under the GNU GPL and I have some questions:

Should one attach a copyright notice on each and every source code file from their project? I think it's a bit ridiculous to claim copyright on a 3 line abstract class. Should I attach a copyright notice only to really important source code files?
Can I not attach the whole standard thingy? Because it's big and bulky and gets in the way... If so, is the variant below ok/enough? 
Copyright year firstname lastname.
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation.

A:

Near the beginning of every file there should be a copyright notice and the following statement (change Foobar to your program's name):
This file is part of Foobar.

Foobar is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Foobar is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

You should also include a copy of the full license text somewhere in the distribution of your program.
http://www.gnu.org/licenses/gpl-howto.en.html
Apparently, 3 line classes are no exception...

