Thanks. What is a "session" in this context?

You gotta ask your carrier that. A session might be ended by a certain amount of idle time.

ASAIK, a session has a maximum length of 24 hours. Since most people don't stay connected this long, it is the time where you connect and then disconnect again.

Let's say you are offline. Then you turn on your internet connection to view your email, and you use 105kB. After that, you disconnect again. Then your data usage would be 105kb for that session. Depending on your carrier, he might charge you for
110kB (charging every 10kB)
or 200kB (charging every 100kB)
or even 400kB (charging every 400kB) <--- pretty bad, hm?

I bought an N900 yesterday off ebay and expect it some time next week. I currently have a blackberry 9000 on a $69 cap and get unlimited net. I will have to switch my cap. I expect I will get about 500MB of data on my new plan

what I want to know is, how much data do you use per month, and how heavily do you use the net?

i called and found out tha i can get 1GB for $10 more... which also bumps my cap up to $550 included a month. and free txt and mms

which also makes me want to ask, will the fMMS app work for me in australia on vodafone? i like sending picture messages, and since i would get unlimited mms im hoping the app works for me

I have a solid rate dataplan. Normally about 3-4gb per month bandwidth usages.

fair bit of data. im sure i could easily use 4GB+ via streaming video, MP3 dowloads ect. but with 1GB im guessing i will have to limit my browsing.
unless i am on wifi

mms should work fine as i use it on optus in australia. as for data 1.5 gb should be fine as long as your not downloading torrents off transmission over 3g... i have 2gb included and that is just enough for me per month and i keep integrated facebook chat/ skype on , and regularly use youtube/ browse webpages, email etc.

I have a 1GB/month fair use cap on 3 in the UK, but it seems that I only use about 25MB/week on average. This is unconstrained usage, but I simply do not perform bulk downloads on the device over 3G (podcasts, video, etc.), and it is hooked up to wifi outside working hours and normally at weekends.

Last week I went abroad and purchased a local SIM and 50MB data topup. I'd used about 28MB of that when I left a week later. Again this was supplemented by wifi, but I did make some Skype calls over 3G, and used GPS/mapping quite a bit.

Obviously I could consume more data, but this seems so typical for me that I thought I'd mention it.

I find i use around 500mb a month, i think my cap is a gig but i find that hammering the net reduces the battery by faaaar too much! i generally listen to di.fm on the way into work, i have bad reception at work so cant listen to much there. I usually have jabber and skype connected all day and then another round of di.fm on the way home.

My phone can usually be close to dead round 11pm dependant on the signal at work but like i said i only use around 500meg a month.