When a separate logo is executed well it can be very powerful - the best example I can think of is the apple computer logo - but how long did it take for them to establish the link between the logo and the company - years. They also had it a little easy, as their logo is a representation of their name i.e. an apple. If you have an abstract company name then you have a bigger task to create a linkage between your logo and company name.
My own opinion here is to make the logo the company name and don't have anything separate. Go for a clean and neat look. When your company name is the logo the brand is being reinforced. Some of the logos I really like are Google, Microsoft, Citrix, Amazon, FedEx - all use their company name in the logo, are very neat and easy to read.
Amazon is particularly clever for two reasons; firstly they tell you their web address (amazon.com), secondly, the arrow shows that they sell from A to Z. Cool.
Novell is an interesting case, take a look at their original "shark teeth" logo - the problem was it was impossible to render on screens of the day without getting the "jaggies" - we're talking VGA here :-) I'm also not sure what it exactly meant, but it's probably a stylized "N". But for those of us hard core networkers who remember NetWare 3, we did love that logo (I seem to remember lots of people sporting shark teeth temporary tattoos at Brainshare one year).
The next was the very short lived "Novell Balls" logo. This was not very popular as it was too large and the rounded balls were very difficult to render nicely on a computer screen in the late 90s. And the inner "N" was hard to see in many forms.
Their new logo is just the company name, neat and clean. Beautiful - especially when you compare it to the two above.
This brings me to an important point in picking company names - try to come up with a name that doesn't have any descenders i.e. letters that drop below the horizontal, such as p and q. It's much easier to have a neat logo without descenders. If you do have descenders, then try capitalizing, or somehow working the descender into the design. Take a look at the logo below - pretty cool use of the descender, and it ties into the company name.