ya i cant comment on that Max Marshall.
Expensive yes, because dev kits cost a bit more, but this is coming down, generally not a deciding factor though.
As for a preferred plaform i dont know?? this is up for debate and is alot down to developer\publisher and the skills of the people working with the various versions.
I think the problem with poor ps3 titles vs the same title on 360 (AC being the example here in terms of fps\saturation etc) is down to the individual developer making the decision that one is their lead platform instead of choosing to develop both as leads. 360 often being the case as its similar to xbox 1 in terms of libs etc and theres alots of game out (360 launched earlier, produced dev kits quicker\cheaper etc), lessons learned during dev, ppl who have developed 1-2 titles already and bring a wealth of knowledge and experience. So its easy to see why 360 is perceived to be easier. Theres as many ppl with ps3 experience, and even less in terms of spu,cell etc. But their catching up fast. I suspect 360 and ps3 games to be on par by this time next year.
What im getting at is that you cant simply port a 360 game to ps3 and expect it to work (example of such can be seen in the common saturation problem, easily fixed but often isnt due to time\effort etc versus port and ship!). These machines are quite similar in terms of what they can do but how you go about doing the same thing on both platforms is often very very different. Only way to code good on multi-platforms is to be aware of these differences and branch the code at these points. I think on SEGA Rally we did a pretty good attempt at this (we had one or two very good coders who really grasped the differences\spu etc), as most ppl\reviewers will say they look pretty much identical on all platforms (but depends on how picky you want to be).
So hope that sort of answers your question.
As for my own personal opinion on which is easier (i dont do much low-level graphics) but from a high level point of view 360 is a bit easier but it does protect you from stuff you might often want to get at, ps3 allows you accomplish this better.