Can I install Lion, and keep my Win bootcamp partition?

Ditto.

Check also this thread:

http://forum.notebookreview.com/apple-mac-os-x/596645-did-anyone-upgrade-lion-mac-bootcamp.html

PS: Can you move your post to the Mac OS X 10.7 Lion sub-forum?

I had the same problem after I upgraded to LION but found a solution.

2 parts of the problem:

1. Can't see the windows 7 partition or Windows 7 not mounted in Lion OSX

2. reFIT (associated with bootChamp I think) was NOT working.
Not letting me choose which OS to boot into.

To solve the reFIT problem:
RESTART YOUR MAC 3 times.
On the third time reFIT finally woke up and started doing its job and I could choose to boot into the Windows 7 partition, no problem. I remember when I first installed reFIT I had to restart a few times for it to work.

To solve the NTFS problem (windows partition not mounted):
Download and install the latest ver of NTFS-3g

http://www.tuxera.com/products/tuxera-ntfs-for-mac/

Once it was installed and I restarted, everything just WORKED like magic.
With the trial version still running, I could copy a file from Mac to Win7 ( Some higher level folders were locked eg. DOCUMENTS, although within documents I could put the file in a subfolder.) AND I could copy a file from win7 into Mac.
There's a 15 day trial to see that you can access/read/write to windows partition. The full version is about $25. Or you can do it the hard way and search for crackz and serials but GOOD LUCK with that one. Just buy it.

Im not saying this is the only/cheapest/best solution, Just saying it worked for me. I know that when I installed Lion and refit stopped working I immediately panicked and searched forums for a solution. I didn't remember the restart 3 times thing.