ok, i did some more testing last night. i turned off the auto-disconnect app i'd been using (which successfully dropped the connection down to 2G from 3G, but i was having the data connection problems described above), phone was set to 'GSM' all night, hopped on the train, went off to dinner at a friend's place, then a few drinks outside a bar.

no access to wifi during that time, and the phone stayed on 3G (or 3.5G as it found it) for the duration. each time i went to use the phone itself, data was immediately available (didn't experience any of the 'no data connection available' prompts i described earlier).

so, everything worked as i'd expect under this scenario, but, also as expected, battery life was an issue. during the six hours or so, the battery was completely drained. was reading e-mails during this time, couple of IMs, checked train schedules and listened to music on the train ride & walk home from the station.

i apologize for referencing the iphone, but this is my previous experience... so, when i used the iphone, leaving 3G on was also not a feasible possibility (edit: from the standpoint of battery life, i mean... battery would run flat in way less than a day). i would turn 3G on when i needed to use the net away from wifi, and switch back to 2G when the phone went back in my pocket. this is the basic functionality i'm looking for with the N900 as well... without losing my data access or making it overly cumbersome to pull the phone out and quickly run an app that needs a data connection.

i guess what i'm looking for is a simple switch to turn off the 3G functionality, so that i can maintain a data connection over the slow but efficient (from a battery standpoint) 2G connection. i would have done this last night, but the phone was set to 'GSM' not '3G' yet stayed in 3G all night. is there a simple toggle available? what would setting to 'dual' accomplish, relative to the above?