Yes you can browse the internet with an EBW1150. The only thing is that the internal browser is not very powerful and will not correctly render new HTML pages. Simple HTML is fine for this device.
I tried that when I was trying to write a Java program to upload local ebooks to my device. As a proof of concept I remember generating a special html page that enabled web surfing. The project then died because of my lack of java knowledge and time.
This is how it worked: the device tries to connect to ebooktechnologies server and asks for a file which is a list of books. You change your OS "hosts" file so that that URL resolves to another IP. Breeno has done that and changed it to point to 127.0.01 (localhost) so that you can upload local content.
The second part is to instead of giving the list of books file, give it a specific file with a link to the internet so that you can start browsing. I think you cannot directly type an URL.
I still have the java files if you are interested in that small proof of concept.
Hope this helps a little...