Jaqui, as long as you use the SSL link to login, your password will be protected by 128 bit encryption (virtually uncrackable). Once here though, you're on an 'open' page resident on one of eBay's unsecured servers, which means anyone with the beanie and brickles to hack in could easily access any or all of these pages. However remote that possibility, nevertheless, I still would not post any sensitive personal info (like my phone number, full name etc.) in these threads.
Actually, the 'leakiest' part of these boards is the login itself...because Canadian PowerSellers have two choices (unlike the Americans who appear to have only the one, fully secured). If you're logging in via the top left link you're secure; if you're logging in via the icon link beneath the U.S. board you will be unsecured. And although I'm not absolutely sure about this, I believe that this unsecured PowerSeller login is a static page (consistently same address) on eBay's server(s). So forgetting about the possibility of a more elaborate personal hack for a moment (presumably logging in unsecurely leaves an unencrypted 'cookie' on your hard drive), it would be very easy for even a 'lite' (read-only) hack of eBay's unsecure servers to identify the unsecured login file. To be on the safe side, always login via the left link, not the right.
Malcom, although I'm now rather paranoid about the security issue here, I'm not that paranoid...at least not yet. However, it may interest you to know that after one of the Security pros had analyzed my system and not discovered any keyloggers or trojan redirects, his first thought was that somehow the unsecured servers of eBay had been hacked, and that this was how the miscreants retrieved the unencrypted file of unsecured PowerSeller logins. We'll never know for sure because eBay would never admit this, but it's at least as plausible as a local system hack.
Let's put it this way...before any of this happened, I experenced no security 'events'--none whatsoever--whistle clean system(s) and 'Net-based work for years--and since I've begun rigorously avoiding unsecure logins throughout eBay's site and these boards, as well as jettisoning the toolbar...well...once again...nothing...nada...nyet.
Entirely circumstantial evidence, but I truly believe that if you watch out for the first 3 potential hazards mentioned in my previous post (Defualt unsecure, PowerSeller unsecure, and Toolbar), you will have nothing to fear* here.
* ...except of course, those random, mysterious, somewhat dopey policy and interface changes.