I switched from Firefox to Flock a few days ago and I love it. It's based on Firefox's code, so all of the plugins (Flash, Java, etc) that work for Firefox also work in Flock, as do many of the extensions. If you have any questions about Flock, its community can probably answer any questions you have better than I can, so I suggest asking there first, though I am willing to take a stab at any questions you may have, so don't be scared to ask!
Now, here is the howto!
Step 1) Make sure libstdc++5 is installed -- it's the only dependency you need. Enter the following command in a console:
Step 2) Download Flock from http://www.flock.com/developer/linux.php
sudo apt-get install libstdc++5
Step 3) Extract the tarball.
Step 4) See if it works.
tar xzvf flock-0.5.12.gz #Note: You have to be in the directory you downloaded Flock in
Optional Step 5) Add it to your Gnome Panel.
Right-click the Panel --> Add to Panel
Select Custom Application Launcher.
Enter the following information:
Any questions? This is my first howto, so be nice! ;p
Generic Name: Web Browser
Comment: Browse the web
Command: Click "Browse..." and browse to the executeable you ran in Step 4. Mine is /home/dan/flock/flock
Icon: Click the icon and browse to the same spot you did for "Command". Enter the "icons" directory, and then select the one you'd like to use.
I'll make a debian package for Flock once I learn how to make them.