I don't know if you can find them, but I have no idea how to get to the login page and/or register account page via some link, on weblogs.asp.net and blogs.msdn.com. A lot of blogs have anonymous comments turned off, therefor you might want to register or login. Another reason is subscribing to new comment, so you'll get an email when a new one is added.
Luckily they're using Community Server, so those locations are the same everywhere. If you want to know, these are the locations.
weblogs.asp.net
blogs.msdn.com
I tried this a while back and IIRC creating a new account was disabled, however it looks like weblogs.asp.net shares member info w/ *.asp.net, so you can create a new account from the other pages as well and it will be shared across the entire TLD.
Regardless, good find...quite a few asp.net bloggers have anon comments disabled so this'll help out quite a bit!
news of the day a grab bag for what's happening in Community Server Eric A. Duncan is good on his word
Dennis van der Stelt lists the default login and create new account page links at weblogs.asp.net and