I have been using openSUSE 11.1 around this time and i have used KDE4 more smoothly, while other software applications are also very easy for me to use, especially in many commonly software applications which are usually used for everyone and has been developed for the appropriate version of KDE4, maybe you want to know which software applications you must use in openSUSE?
Actually, there are 10 kind of software applications in openSUSE are my most commonly used and almost related to networking, if you are also connected to Internet from your machine, these software applications should be able to meet your requirement either MSN or Twitter can be easily to use in openSUSE. Now, please take a look as following content.
1. Firefox: It's a internet browser that will be able to install many different extensions, themes and plug-ins, this browser has become the second largest in the market, and also has prepared to go beyond Microsoft IE.

2. Thunderbird: That is a mail client software which provides different protocol to fetch mail such as pop3, imap4, you can also integrate AD domain via LDAP. It's like Firefox will be able to install many different extensions, themes and plug-ins.

3. FileZilla: The purpose of this application is to be a ftp client such as gftp, but you can transfer file not only using ftp protocol but also using ssh protocol.

4. Gimp: A part of designer maybe try to search graph design program in Linux such as Adobe Photoshop, but don't know which one can replace Photoshop in Linux, Gimp is a professional image design application that can provide so many functions that we can use it to replace Photoshop.

5. KTorrent: It's really a important application for us, you might be want to say why? That is because so many document and file we can download from the Bittorent and KTorrent is one of bittorrent client in Linux, so if you want to download something on openSUSE you have to try it.

6. Amarok: Why i suggest this application? That is because you should not be a lack of music in your life, however it is the best application to play music from your machine, Last.fm and mp3tunes...

7. K3b: It's a multiple CD/DVD burning application, the main window presents the user with multiple CD burning scenarios to choose from including Audio CD Project, Data CD Project, DVD Data Project and CD Copying as below, you can also use different theme in it.

8. Pidgin: Pidgin is a chat program which lets you log in to accounts on multiple chat networks simultaneously. This means that you can be chatting with friends on MSN, talking to a friend on Google Talk, and sitting in a Yahoo chat room all at the same time.

9. Choqok: Choqok is a Free OpenSource fast, efficient and simple to use micro-blogging client for K Desktop Environment. The name comes from an ancient Persian word, means Sparrow! Currently support Twitter.com and Identi.ca micro-blogging services, you can use it to log in to Twitter and Identi.ca at the same time.

10. OpenOffice: The OpenOffice.org project is primarily sponsored by Sun Microsystems, which is the primary contributor of code to the Project. That is a office application and allows you to use it to read/write .doc, xls, ppt files.
