Just to finish this off, thanks for all the help again.
I figured out that it was a missing clustered index and defragmentation (or fragmentation, whichever way you look at it, i think specifically data fragmentation), that was the culprit.
From the graph, my theory was that 2 ad hoc INSERT processes were trying to insert into the table. For some reason, since it was a heap, it was trying to escalate it's lock (i'm assuming at the page level), to a table level lock. Since the two processes occurred within milliseconds of each other, it each grabbed a page, and were both trying to escalate to a table-level lock.....hence, DEADLOCK.
With the clustered index, i was hoping that it grabbed a page-level lock (or something more granular than a table-level lock), and the lock was held quicker b/c SQL knew exactly where to insert the row. and thus prevent a deadlock..
Hopefully that reasoning made sense..from a technical persepctive.