Yes, Wipro is a very good organisation to work with. For Online preparation of Wipro Placement exam. Try the latest Mock Test made by Youth4work. CLICK HERE to get the mock test.
Yes, please email Wipro regarding the status of your offer. Make sure, you have at least one formidable offer in hand. Don't risk too much assuming that CTS will send you the offer and don't ignore the Wipro offer.