Indeed, I could see funding as a rather toxic topic. However, I think it might be wise to tackle it nonetheless. I would rather openness to inspire trust; and, even though it may be little more than a gesture, it might dispel some concerns that an RSA-style situation could arise where encryption is weakened for a price.
Admittedly, I do think that putting donations before development may cause a rather tricky situation. Again, I have little experience to speak on, but I have heard it said that users will merrily put up with any rough edges found on a free application; after all, it is free! However, if they pay even a dollar, a sense of obligation is shoved onto the developer for future support, expectations suddenly get set that may or may not be realistic, and I would imagine such things can be problematic for those hoping to donate their time and expertise.
I did have what may be a rather silly question: would any proceeds gathered go to the TrueCrypt developers? Of course, that assumes anyone could track down the creators, so this may be a bit more philosophical of a question, but I’m curious. (I confess, I am green behind the proverbial ears when it comes to FOSS, so I offer my apologies if this is a blatantly daft wondering on my part.)