mindhunter77 - If vB Optimise is reporting an issue with eAccelerator, chances are eAccelerator not working correctly. Might wanna check your setup, or ask your host for assistance.
Vitaly - I make no claim to instantly reduce server load, but it may impact it if vB Optimise has done a lot of optimisation ontop of what you had before, so a reduction of two queries wouldn't be significant enough - that said it depends on the amount of users you have active and your server. What cache method are you using?
KevinL - I'd agree, XCache does seem to be slightly better than memcache, mostly with page generation time
As for what I intend to do with vBSEO, the same as vBAdvanced really, optimise.