EDIT: What we have gathered:
- Poirot confirmed the time of death as being during the party when asked:I have been told that the mild onset of what they call ‘rigor mortis’ confirmed that Comte de Cavaignac was murdered 3-4 hours before he was examined, which would place his death in the middle of the reception from 19:00 to 22:00, yes. He was seen that night at 18:30, shuffling to the office with what was described as… I suppose you would say, ‘brooding’ expression, as if he was dealing with something of the utmost importance.
- Further questioning requesting information on the seeming discrepancy between Poirot's head count,...ten people, as well as the wife...
and the number of actual guests counted has remained unanswered as of yet. It is likely that the unaccounted for guest is Poirot's mystery benefactor.
- Due to Poirot's description of the wounds as "shallow" the likelihood of the guilty party being someone with little physical strength, such as the wife, Valerie, or the elderly couple increases. However, at this time there does not seem to be a way for the wife to have killed him, due to the time of death being confirmed.
- Suspicion about a conspiracy cannot be discounted at this time either. Even if the wife could not have committed the murder directly, she is suspicious for ordering the servants to leave the victim alone, and the fact that a pair of her gloves were missing. Personally, I notice a possibility for a framing plot beginning to manifest here, so the wife may be innocent after all.
- The anti-social couple are also suspicious, as their strange actions may indicate guilt over involvement with the murder. However, Poirot has said that they were confirmed to stay in the hall all night, and we have no precedent to compare their actions to. They may just be anti-social.
- Finally, as I stated, speculation on the motive is going to involve a lot of guessing, because a murder mystery, even a Fair-Play Whodunnit, will always release the motive information last.
- As noted by YankeeWhite, the fact that Jacqueline was wearing a white dress lowers the chance of her committing the murder; though the wounds were shallow, there would likely have been blood stains. (Besides, as Dryu said, she is too obvious) Similarly, Valerie, in line with my former musings, is increasingly likely to be the direct killer due to her red dress. (However, for meta reasons I don't think things are going to be quite as simple as we think.)
- Poirot has still not resolved the guest discrepancy, and it seems very likely that it will turn out to be important. Also, Yankee has attempted to get the "strange numbers" from the back of the Swiss bank card found in the victim's pocket, but all remains quiet.
I'm going to be gone for about 24 hours after this, so I hope you guys can put this info to good use without me. Catch you all later, and good luck!
EDIT2: I have returned and am in an awesome mood after kicking ass on that test. Just finished updating the most important bits of info I saw. I need to go catch up on the posts in other sections, then I will rejoin you here and get anything I messed added in.