IMO any contact is great and gives you the opportunity to keep communicating. This is especially so as you never know what's going on through this process.
My son has received letters from about 50 schools. Some have lead to more and more contact. Most have lead to nothing. But, again, you never know.
For example, one school wrote constantly, sent media guides, junior day invitation/visit followed by phone calls, hand written letters and then...... nothing. Still nothing, despite several follow up attempts by my son.
Another school sent a form letter. It was addressed "Dear Prospect". They crossed out prospect and wrote in his name. My son sent back a thank you letter, mostly out of courtesy and heard nothing further (for about 8 months) and then without any further contact, recieved a hand written note "inviting" him to the team (no scholarships at this school so none to discuss). Apparently they had seen him at a camp, never spoke to him, no other contact and then an "offer". We've got no idea what took place.
I have found the college baseball recruiting process to be the most inexact science I have ever encountered. If I recall, I think I said in one of my first posts that it reminds me (in the worst sense possible) of high school dating.
I don't get most of any of this, except to keep trying, keep contacting schools you're interested in, keep getting seen and who knows what this LSU letter means. Don't get too high or too low, just use it to keep in contact and best of luck!!!!