By Sean Maguire

Joining an all-star cast of investors that includes Guy Kawasaki, founder of Alltop and Dallas, TX billionaire Mark Cuban, founder of Broadcast.com; SlideShare, Inc., the world’s largest online slide sharing community announced it has secured $3 million in Series A funding, led by Venrock.

The funding enables SlideShare to expand operations, fund continued product development and accelerate its subscription base.

A free service, SlideShare is the “YouTube” of slide show sharing; allowing individuals and organizations to easily upload and share presentations and generate leads. Files can be tagged, downloaded and embedded into blogs, websites and social media platforms.

As part of the round, SlideShare adds Venrock General Partner, David Siminoff to its board. “Our use of the Internet is evolving from consuming and sharing text-based information – like email, news and blogs – to visual communication, using imagery and video,” said Siminoff.

First MySpace announced data portability, then Facebook announced Connect, and now Google has Friend Connect. Each is making it easier to share profile information from one social networking site to other web sites (and hoping to be place you go to do that). Google’s Friend Connect was announced today.

To add social networking features to any web site, you can get code from Google (although, unfortunately, the site does not work until tonight) and pick which features you want to add. The code will allow people register on your site, invite other people, import friends lists, see who else is on the site, and post messages and reviews.

Yesterday MySpace announced that you can use your MySpace profile on other sites. Not to be outdone, today Facebook announced their version. It’s called Facebook Connect and it’s a good sign that data portability is catching on. Especially because Facebook usually doesn’t follow suit when it comes to sharing data (unless it’s for advertising).

Facebook Connect was announced on the company’s developer blog.

Privacy is a big concern as it always is with social networks. Free means you give up personal information so you can be on the site. If you change your mind, getting the information off could be tricky. Also, each site has its own privacy policies.

Each time you sign up for a new site you create a profile which is unique to that site. You’ve got to upload a picture and fill everything out. It’s a pain to keep up with it all, which is why I haven’t yet added my picture to my Digg or LinkedIn profile.

MySpace has launched the Data Availability initiative which can make MySpace your home base for profiles. With this new initiative you’ll be able to integrate elements of your MySpace profile on partner sites that so far include Twitter, eBay, Yahoo! Instant Messenger, and Photobucket.

It’s been nearly four months since MySpace announced a joint agreement with 49 state Attorneys General to protect minors online—and now Facebook’s finally gotten around to signing on. CNET reports (emphasis added):

In the deal, the social network has agreed to develop age verification technology, send warning messages when an under-18 user may be giving personal information to an unknown adult, restrict the ability for people to change their ages on the site, and keep abreast of inappropriate content and harassment on the site.

When MySpace and the AGs inked the “Principles of Social Networking” (which I still say should have been named “Principles of Privacy for Minors in Social Networking”) guidelines earlier this year,