Before i bought it, i thought the boot time will be the iLiad's weakest point.
Now, i don't even notice it...
When i wake up in the morning, i flip the switch and keep it on until i leave the flat or put it away. When i'm out and about, it's always on unless i'm about to pocket it or stow it away in a bag, at which point i turn it off. It endures a day and a half to two days on one battery charge that way.
Seriously, unless you often have some critically urgent note taking or reading to do at totally unexpected times, you won't even notice the boot times. You just have to adjust to a slightly different way of working with it than is usual with PDA's, phones and other readers - it's more similar to the way you use your computer (i.e. you keep it on unless you're sure you won't be using it for a longer period of time).