I do like the wider format, and the filtering is nice, but I tend to agree with most of the above points, like having a overview of all trades and the confirmation window and the trade list disappearing if you cancel out. Heck, I'd even prefer if we could search for people able to accept a very specific "card 105 for card 436" trade to ease the sheer amount of time it takes to find a trade I can (and want to) actually complete. Sort of like how most MMOs do their auction houses.
But that's not my main issue atm sadly. Currently I have to refresh the page to get out of an incomplete trade window, because the Cancel button is broken for the vast majority of trades. If I mouse over it the pointer will change to the interact form for a moment, then start flashing between "pointer hand" and "arrow" quickly until I refresh the page.
It looks like a broken script to me, in all honesty, and I have no idea why it works occasionally and does not the rest of the time. I'm accessing the site through Firefox btw.