It realy depends on how pixologic what their software to fit into his or her pipeline. We all know what zbrush is realy good at and for that its gained respect in the CG world. I was lost without a conventional modeler as I wanted some basic tools to make precice hard serface objects. The simple tools that I thought id need soon extended to many tools to get the job done in a external modeler. Even Zbrush zsphears didnt meet demands due to its method of topology used.
If pixologic added these vast tool sets to become a mechanical and organic modeler then yes it would be simply great, but I dont think it would do zbrush justice to put a half attempt at trying to do somthink els unless they where very solid and could compare to other 3d modelers. longer wait ppl.
Pixologic would have to have more that one view port with real perspective views. They would need to implement a modifier control, X,Y,Z one like in hexagon would be perfect. You would need grids, numberic cords input, Extrude, split polys. full control over faces, points, edges just to mention a few of common tools and methods used. Its would take a long time to put these features in, maybe v3, 2 years or so from now.
My point is software is better to excell in somthink than be another clone to what other software can do at its best. zbrush looks to keep this trend in v2.5 originality.
Just a few reasons for somone like me to perchase zbrush 2.5 over other software.
Price
Great community and support.
DVDs , Gnomon, Digital Tutors, and free tutorials avalible here.
Zscripts, plugins
Free flow ,artistic ,intuitive and fun.
High poly sculpturing/ detailing.
3D texturing plus use of alphas in full 3d.
Zspears to create extreemly fast base meshes.
Ability to re-toplology the serface, rig and pose the serface.
Reposing the model with ability to deform mesh at the same time.
Mesh extraction to make clothes and armor.
Did I mention fun!
For the hobbiest new to 3d this is a nice start too. The fully coloured printed manual is simply top class. exsamples, tutorials and zscripts will keep you wanting more. Any added feature we dont know about is a bonus as zbrush has already push the boundries with the features seen so far.