By Gerry Shih and Edwin Chan SAN FRANCISCO (Reuters) – There was a time when Twitter strove not to end up like Facebook. Now, the one-time Wall Street darlings inability to replicate its bigger cousins success in mobile and online may be what holds it back. Wall Street remains divided over Twitter as the seven-year-old company prepares to unveil only its second set of quarterly numbers on Tuesday. Eleven of 31 investment analysts polled by Thomson Reuters rate it a sell, outnumbering the seven who deem it a buy. The rest have a hold rating or its equivalent.