They both can essentially do the same things if you know how to make that happen. I've been told the iPhone is a bit easier and more intuitive for someone who isn't really up on techno-gadgets though.

WIRED did a great product comparison between the two here:
http://www.wired.com/geekdad/2009/08/great-geek-debates-iphone-vs-blackberry/

and this video will show you the phones 'live' so you can see what they look like to help determine.

This is the iPhone Vs. Blackberry Bold:

http://www.youtube.com/watch?v=Fl7cqFQatP4

And this is the iPhone3G Vs. the Blackberry Storm:

http://www.youtube.com/watch?v=xuEerMCAlx0

My recommendation is to hit a Best Buy or Fry's Electronics where they will likely have demo models out that you can play with and see which one works best for you when you actually get to use it. These are much too expensive of products not to take them for a virtual test drive before you decide which one has the features you need to organize your social life!

A lot of people get really worked up when it comes to picking a phone... some will even get quite angry if you suggest that you should even consider the other brand. Ignore them. There is no such thing as 'the perfect phone for everyone'. What you really want is the right phone for you.

The Blackberry is a fantastic device for people who love email and messaging. There is nothing on the market that does it as well. If someone sends you an email you get it instantly. And the built in keyboard makes replying to it amazingly quick and easy. The Diary and Contact list work really nicely as well. If you're the sort of organised person who uses Microsoft Outlook to keep on top of things then you'll adore the Blackberry. It is like carrying your outlook schedule around with you in your pocket.

On the other hand, the Iphone is a very nice device as well. It will do email like the blackberry, but not quite as slickly. It also doesn't have a physical keyboard and uses the touch screen instead. This does work well, but its slower, and you'll find your email is likely to be shorter its a bit of a pain to type long emails. Where the Iphone does excel is Web Browsing. If you use facebook to organise your social life a lot then this will be a boon. The Iphone also has a wide variety of applications (also known as apps) which can recommend restaurants, find places to go, book tickets etc..

I'd probably avoid the Blackberry Storm though.. it was their attempt to build a blackberry like an iPhone. Unfortunately it manages to put the worst bits of both devices together in one package.

I really want to say that there isn't a difference. I'd like to say that either a blackberry or an iPhone can be used (with additional software / apps) to organize your social life.

To me, two things are important to organizing a social life. First, you need to know who everyone is and how to get in contact with them. This is done (on either device) with a solid contact list. Next, you need to know where people are and what they're doing. This is where the iPhone edges out the Blackberry.

Both phones have an application called IM+ that can be purchased. This is a really (really) great app that lets you stay in touch with friends via Twitter, Facebook, Google Talk, MSN, AIM, Skype, etc. Half of the social battle is being available when (and how) people want to talk to you. If there's a party, you don't want to miss the note because someone posted it on Facebook rather than Twitter.

Both phones also have a variety of applications that allow you to seem "cooler" than you are. Between drinking games, to movie and restaurant reviews, to conversation starters, it's pretty easy to "look" cool if you know the right things to do, the right places to be and the right things to say.

In my mind, the thing that really seperates the iPhone from the Blackberry in the social arena is how GPS is used. The recently released iPhone TomTom app allows me to look up a contact and navigate right to them. If I'm at a party and my friend Lisa says "Rob, I'm at a great party at tktktk", I can click on her and navigate right to her. Better yet, if I'm at a great party and want to let everyone know where I am, there are a variety of ways for me to send out the message using an iPhone. This functionality is available but significantly lacking in current Blackberry models.

http://www.youtube.com/watch?v=uVGbJHh0otw

This is an eternal battle. iPhone owners swear by their phones. Blackberry owners swear by their phones. I know someone who switched from Blackberry to an iPhone and within a week or two switched back to her trusty Blackberry. I also know people who are very loyal to their iPhones and wouldn't think to use a Blackberry. It's head-to-head technology at it's best!

I'd say, through my experience with both phones, that what you are looking for - social organization - is best served on the iPhone. I have a Blackberry and they are not as well-equipped to handle a bunch of different social applications. I've tried on mine and all it did was slow the phone's operation down to frustrating levels.

Corporate executives will pick the blackberry almost every time. An article on TechCrunch.com explains why the Blackberry wins out in business, but it also supports why the iPhone is better for people like you, who have a more social need rather than a business need. A link to the article is below:
http://www.techcrunch.com/2007/07/25/iphone-v-blackberry-side-by-side-two-week-comparison/

I'd say it actually depends on how complicated your social life is. I think most iPhone users think it's great for all things social, and for them they're probably right. However, I'd argue that it's too difficult to organize a complicated social life without a keyboard. I personally do not have a physical keyboard, but I have a stylus that's still 90% as fast (HTC Touch Diamond). When it comes right down to it, I simply could not live with an iPhone.

blackberry would make my social life easy because it is less costlier and easy to handle.