Once you have a bit of SharePoint experience under your belt you’d really like to consolidate that and let people know via certification. The best options are the following 2 certifications available from Microsoft:
70-667 - TS: Microsoft SharePoint 2010, Configuring
70-668 - PRO: SharePoint Server 2010, Administrator
However, if you come from the world of SMB and SharePoint Foundation things are going to be a little more tricky than simply sitting these exams. This is because both of these exams focus not just on SharePoint Foundation but also SharePoint Server. This means you are going to need to know about not only SharePoint Server configurations but also things like Network Load Balancing, Virtualization, and so on.
70-667 is perhaps a more basic exam with a number of questions presented in sequence. You can generally return to any of the questions at anytime and review your answers. 70-668 is little different in that it gives you scenarios that you need to read, then you are expected to answer a few questions based on the scenario. Once you have answered these questions you can’t return and review them. Thus, you only have a limited time to read, digest and answer what is presented in each case.
If you are coming from an SMB background and SharePoint on SBS you are going to need to learn about SharePoint server. The best suggestion (apart from my Guide and installing it on a VM) is to have a look at these publications:
Professional SharePoint 2010 Administration By Todd Klindt, Shane Young, Steve Caravajal - http://astore.amazon.com/c00ef-20/detail/0470533331
Microsoft® SharePoint® 2010 Administrator's Companion By Bill English, Brian Alderman, Mark Ferraz - http://astore.amazon.com/c00ef-20/detail/B0043M52KY
Not that I have read it but there is also the following book specifically focused on the 70-667 exam:
MCTS Self-Paced Training Kit (Exam 70-667): Configuring Microsoft SharePoint 2010 (Training Kits) - http://www.amazon.com/MCTS-Self-Paced-Training-Exam-70-667/dp/0735638853/ref=sr_1_3?s=books&ie=UTF8&qid=1317964888&sr=1-3
At the end of the day both the 70-667 and 70-668 are focused on SharePoint Server but if you know your SharePoint Foundation stuff and are prepared to learn a little about SharePoint Server then you should be able to pass the exam and add these certifications to your roster.