I hear that borg characters are superior due to the "Borg Nanites" and "Efficient Captain" traits. I know that "Efficient Captain" can also be selected with other races, but "Borg Nanites" is exclusive.
Oh well, I guess I will be waiting until it goes on sale for $200 (or less).
The Nanites are cool, not a given though, you have to select it as one of your traits when you make one. Also it's very similar to Mind Meld if you roll a Vulcan. I actually have both, a Vulcan/w Mind Meld and the lib/borg w/ Nanites, however I find the Nanites gets resisted a lot. Basically it stuns/slows the target for a little bit of time. Nothing all that great, although it is nifty.