Evidently, and understandably, the Labour Party have leapt on this with a 'you too!' argument, and their glee is helped along by the names of the donors as well. After all, when the Rothchilds name appears what Labour person wouldn't inject a bit of class warfare into the mix? Just to add a 'you too' response to their 'you too' I would say this. Take a look at the Co-op Party. How many Labour MPs, up to and including the Prime Minister receive money through that party that is entirely untraceable? I know of Labour MPs who declare nothing on any Registers but are bankrolled by the Co-op. This is not to say that anything dodgy is going on with the money, just that the system of declarations is in mess. If you want to reduce the number of 'sleaze' allegations then fix the system of how and where financial contributions are to be declared.
One of the first principles of data-handling and designing databases is the removal of obvious repeated data. Currently we have a system where legally a donation must be declared to the Electoral Commission, and, under Parliamentary rules, must also be declared on the Register of Members Interests. The Register is available in electronic form as too is the Electoral Commission so why does the former not simply link to the latter? After all, the rules governing what level of contribution should be registered are identical in both cases.
Of course this would do nothing for the current questions surrounding Osbourne which are more about the grey areas of what constitutes a donation to a person and what constitutes a donation to a party where someone says 'I'd like X to receive benefit from this money'. However, I seriously doubt whether all three of the main parties have not had situations like this multiple times. When someone is tapped for money it stands to reason that how it might be spent will be mentioned, and as I said, the reaction to Osbourne is driven by an instinctive 'you too', argument rather than something that is a matter of principle. It could also easily backfire if a letter emerges pointing out where someone would like a donation spent within the Labour Party.
The point though about data repetition is one that is important. As long as their are two sources for finanical contributions then there will be times when the two do not match up which will give rise to stories. Failing to register a donation is one thing. Registering it as per the law and then failing to repeat the data elsewhere should not really be a story. It won't get rid of funding rows, but it would reduce the number of cock-ups that become seen as conspiracies.
Update: Just to clarify. When I said the Register should link to the Commission I meant that it should just refer interested parties to other. Electronically this would be a hyperlink to the Electoral Commission. What I did not mean was the databases themselves should be linked.