Interesting. It looks like its a cover over the existing monocoque. Shape and additional height suggest that it is a cowling to divert airflow over and around the driver. It also extends over the nose cone, but likely wouldn't impede removal of it should that be necessary during a race. Not that that ever happens to ferrari!
Location: Covilhã, Portugal (and sometimes in Évora)
Post
Personal opinion...it a cover used in order to change the nose shape.
If you look at the rear of the nose cone (on top) the nose seems to be in a concave shape....this can creat some downforce in this postion without creating to much extra drag.
Now everyone might ask why not build a new nose cone?
The thing is that they want the nose to interact with the front of the monocoque (which is still in a little of a concave shape). But the problem is that if they were to build a new monocoque just for this new "aerodynamic" feature, it would have to go through the FIA crash test cause there is a change to the monocoque design. Using the kind of cover they are able to change the aero configuration of the nose and front of monocoque without having to build a new monocoque.....avoiding the FIA crash test.
forget about the nose-cone! theres definetly something theyre hiding underneath the cover, something new in the suspension department. the curve of the cover is right over pushrod connections to the monocoque, which makes me suspect that its not about the nose come. but about the suspesion.
Further more, Ferrari would never release such an ugly nose!!! this isnt Williams. there is no need for the downforce(if any that the new shape would produce, the amount that it would create would not overcome the aerodynamic disadvantages of the cover.
The revised "nose" is actually the old nose with a fairing added over the top section of the nose and monocoque. there are several theories about this set up, low drag aero for Monza, secret suspension testing or preparation for 2005.
Low Drag
As the device was tested at Monza (and not at the slower fiorano for example) this theory holds a lot of water. The higher section in front of the driver could work to lower drag by streamlining the messy cockpit area. Ferrari have previously tested windshield set ups for Monza using folded clear Perspex shields, rather than the long opaque set up seen here. It could be thought that the design is too large to act act a simple deflector to clear the driver\lower drag. Should Ferrari run the fairing, protests would almost certainly be heard, the FIA could deem the cover raised bodywork outside of the regulated areas and inhibits vision.
Secret Suspension
As the fairing covers the area over the front suspension (I.e rockers and dampers etc) it could be used to hide a new development. I doubt this is the case as the mechanical parts are placed well ahead of the drivers feet inside the monocoque, placing them above the monocoque would be less aero efficient and could also impinge on the regulations ensuring the foot wells are clear of obstructions (for the safety of the drivers legs)
2005 development
As the front wing has been raised for the 2005 season, ever higher noses\chassis will be required to allow the front wing space to work. The fairing used in Monza would effectively replicate the top half of the set up, perhaps used to prove to the drivers that their vision or comfort (from buffeting) would be unobstructed. However the testing would not confirm anything aerodynamic as the chassis is effectively deeper, not simply raised. Also early release of one of their ideas would be counter productive if every team went off and tried it.
Overall I would put my guess on the low drag set up, rather than a weirder conspiracy theory.
The development of the original F2005 for the orginal 2005 rules has been halted. as has devleopment for the F2004. However the revised 2005 rules (being clarified this week) will demand some new approaches for the front wing height. This new nose "perhaps" could be the first inkings of a major jump in the height of the nose to clear space underneath for the wing to work. so the 2005 theory coudln't be discounted totally