So excited am I, here's the announcement from Ilya Ryzhenkov. The full thread is here

Hi,
Here is updated information about ReSharper 4 public availability.
1. Nightly builds are planned to start publishing tomorrow (in about 24 hours),
when it will be February 15 evening here. Our apologizes to those who live
ahead of our time
It may very well happen that we delay public builds if we find critical problem
in our product. We hope you understand. We won't delay it "just in case".
2. No stable EAP builds in near future. We have to do a lot before we begin
stabilization phase. However, we use current development builds all the time,
so any critical problem will most likely be fixed within a day or two. After
all, we are going to open public builds because YOU asked for it
3. If you are going to download nightly builds, it is HIGHLY recommended
to register in our JIRA issue tracker. We will ask for additional information
for exceptions and problems reported, so we want to talk to someone other
than Mr. Anonymous. Actually, we usually just ignore anonymous exceptions,
if they are not plain obvious, because it is almost impossible to reproduce
them without additional information. When you complete your registration
in JIRA, please include your credentials in ReSharper exception submission
dialog.
You can read more about our issue tracking policy here: http://www.jetbrains.net/confluence/display/ReSharper/ReSharper+Issue+Tracker
4. Information about what to look for in ReSharper 4 and what features are
ready or not will be available simultaneously with first public build.
Thank you for your interest in ReSharper 4!
Sincerely,
Ilya Ryzhenkov
JetBrains, Inc
http://www.jetbrains.com
"Develop with pleasure!"