ebook for rss, manga, and battery life ?

[allw]

Hello,

I'm the current owner of a bebook under openinkpot which work quite well.
What I really appreciate in OI is the ability to leave it on and go back several hours later with no impact on the battery. Now I can't imagine having to put it to sleep each time I have to interupt my reading !
Is this feature common now on other device ? I could'nt find much information on it ?


Why would I want to change me ereader ?
Well ....When I read about the new kindle 3g+wifi, I was thinking that it would be great to be able to get rss feed on the go - from anywhere.
Currently I'm not reading RSS feeds on my ereader, because I think it is too a hassle to fetch them, create, remove the SD card, copy, put back ...everytime I want to read news. Reading them on the pc is faster.
But ....if used over 3g, that would be much confortable. (http://fr.feedbooks.com/news)
Wifi could be a solution too ...but only when at home ...
Unfortunaly Im in France .....so ....no whispernet ! So I guess I'll go wi-fi !


The last main use (apart from classic reading - mainly old essay) would be manga reading, but I guess that it should be better than my 4greyscale bebook ! But a very interresting feature is the display of % of reading for each book when browsing among the books. It allows to know at which book you have stopped ! Does that exist on other OS ?

So the main point im looking are :
Battery life (including stop and go without manuel sleep buton)
wifi (3g?)
Epub would have been a "plus"

The device I was interrested in was the kindle 3 as you would have guessed, but there are a lot of ereader with wi-fi now .....and I could have any information on the power management policies !

I'm open to any comment regarding that use (or even suggestion for a "better use" )