I was looking at the block #339174 on blockchain.info "unconfirmed-transactions" there were over 3350 unconfirmed transactions.

It took 49 minutes to solve this block & the size was over 1700kb. The block size after solved was 487.27KB & 1549 transactions were confirmed.

What happens to the other 1800 unconfirmed transactions? Do they have to wait until the next block or even longer? It seems the large block size is delaying transactions more and more right?

http://i.imgur.com/02ERS9W.png