As far as I know nobody has yet made an analysis about the Facebook Finland network with precise data.
I managed to get my hands on some Facebook Finland network data, and as far as I know it is entirely accurate. Meaning that it should represent quite accurately what they have in the real database, and there are no intentional errors and corrupt entries in it.
The data also allows me to do some comparison to IRC-Galleria's current data and perhaps even draw a few conclusions.
All data is a snapshot from 19 january 2009 and should be accurate enough.
Facebook Finland Network data contains all accounts that claim to belong to the "Finland" regional network. However such a claim can be made by anyone. Also people can have multiple accounts. Bands have accounts. So do companies. And imaginary entities like characters from TV shows or cartoon figures. This means that not nearly all the users listed in the Finland Network are actual people. It is simply everyone who claims to belong to the network at all - with no filtering what so ever.
IRC-Galleria data is more "pure" in that sense; all of it has been either verified by a real cell-phone number or manually screened by an administrator person. There are still a few hundred known fakes in the data, and a probably a few hundred unknown ones.
Facebook data doesn't know all of its users' gender, which I guess is a result of inanimate objects and such being capable of having their own Facebook accounts. While IRC-Galleria data is gender-precise.
All data in both cases have been provided by the companies directly.
IRC-Galleria data is publicly available here:
http://irc-galleria.net/dob.php
(as pointed out in the comments. Edited & added on Jan 20th)
Some stats from the Facebook data:
* Finland Network is about 927,530 users strong
* Males represent 363,120 users or 39.14%
* Females are the clear majority with 530,510 users and 57.19%
* There are 33,900 entities of unknown gender, or 3.65%
* Largest age-group for Facebook Finland is the 25 year olds with 54,100 accounts
* The ONLY age-groups with more men in them are the 64 and 65+ year olds
* Oddly enough there are 14.81% of users by the age of 63 with unknown gender
* and 16.13% of 61 year olds with unknown gender
* in 14 year old the unknowns only represent 0.63%
* The 25 year olds have most entities with unknown gender; 2180
Stats from the IRC-Galleria data:
* IRC-Galleria data only contains data for 12 to 40 year olds, not extending as high up as Facebook data does
* IRC-Galleria is 506,751 users strong
* About 7 thousand users are over 40 and thus not included in any of the following stats
* Females dominate again: there are 257,061 females to 242,025 males
* Largest user group is the 16 year olds with 47,705 users
* While the average age is still well above 20 at 20.41 years
* In all the younger age-groups females dominate, until at 21 years of age the tide turns and from thereon males form the majority
* The biggest difference is in 15 year olds with clear female dominance of 59.14%
* While after the tide turning 30 year old males form a majority of 68.57%
And here's the real beef, some charts that chew through the data.
Each image opens up to a higher resolution version for better examination of the data. All charts were made with Apple Numbers (which did beat the hell out of excel for this task):

Image: Facbook Finland Network by Volume, Age and Gender

Image: Facebook Finland Network by Gender distribution and Age

Image: IRC-Galleria by Volume, Age and Gender

Image: IRC-Galleria by Gender distribution and Age
And the Grande Finale:

Image: Facebook Finland Network vs IRC-Galleria on the same scale
I am not going to share the specific numeric data with you on this post. But if you do want to get it; feel free to contact me directly, or leave a comment.
..and then for some conclusions from all of this:
- IRC-Galleria is a service used by "young girls and old men" ;-)
- Facebook seems to have a whole lot of fakes and non-people profiles in the Finland network; if you compare some age group masses to the actual population structure, it doesn't quite add up.
- IRC-Galleria is clearly a youth service, where as Facebook is more used by folks that are generally 4-8 years older
- Finland seems to have an odd "business networking inside Facebook" effect that draws many senior professionals in there. (just a theory/idea)
- Facebook's data shows weird stuff about older males; they use it clearly more than females of the same age, wonder why is that? Grand daddys more adaptive to the Interwebz than grannies?
- The obvious: Social Media services are very much a Girlie Thing. The female dominance in the user figures is quite evident.
- Facebook has been way more successful in attracting females of all ages than IRC-Galleria has. This is quite obvious from looking at the both services in the same scale chart: the violet-color females are so much more "thick" and present in the Facebook demographics.
- Final interesting fact: according to my sources IRC-Galleria is about 6 times better than Facebook in monetizing its users. If Facebook would be equally good in monetization they would make over 2 billion EUR of annual revenue, which they certainly do not achieve quite yet.
I did this whole numbers play without really considering much about what facets in the data might be the most interesting.
How do you find all this, and is there anything useful or insightful in it?